molecular phylogenetics of the neotropical electric ......freshwater fish are particularly diverse...
TRANSCRIPT
Molecular Phylogenetics of the Neotropical Electric Knifefish Genus Gymnotus (Gymnotidae, Teleostei):
Biogeography and Signal Evolution of the Trans-Andean Species
by
Kristen Brochu
A thesis submitted in conformity with the requirements for the degree of Master of Science
Graduate Department of Ecology and Evolutionary Biology University of Toronto
© Copyright by Kristen Brochu 2011
ii
Molecular Phylogenetics of the Neotropical Electric Knifefish
Genus Gymnotus (Gymnotidae, Teleostei): Biogeography and
Signal Evolution of the Trans-Andean Species
Kristen Brochu
Master of Science
Graduate Department of Ecology and Evolutionary Biology
University of Toronto
2011
Abstract
Gymnotus, the banded electric knifefish, is a diverse genus with a range that extends from
Argentina to southern Mexico and includes species distributed both east (cis-Andean) and west
(trans-Andean) of the Andes. Each Gymnotus species exhibits a distinctive electric organ
discharge (EOD), used for communication and navigation. Here, I present a new molecular
phylogenetic hypothesis for 35 Gymnotus species based on two mitochondrial (cyt b and 16S)
and two nuclear genes (RAG2 and Zic1). I found that the trans-Andean species are distributed in
four distinct lineages with varying amounts of divergence from their closest cis-Andean sister
taxa. I suggest that not all trans-Andean species evolved as a result of the orogeny of the Andes.
I evaluate EOD phase number evolution in Gymnotus and find a trend for reduced phase numbers
in both cis- and trans-Andean regions. Finally, I suggest hypotheses to account for the patterns of
EOD phase number diversification.
iii
Acknowledgments
This thesis would not have been possible without the advice and support that I received from
numerous sources. First, I would like to thank my supervisor, Nathan Lovejoy, for his helpful
insights and continued support. My time spent in his lab has helped me to develop important
skills as an independent researcher that I have no doubt will serve me well in the future. I would
like to thank my supervisory committee members, Hernan Lopez-Fernandez and Marc Cadotte,
for valuable feedback and advice. I am also very grateful to the members of the Lovejoy lab,
Megan McCusker, Eric Lewallen, and Devin Bloom for their guidance and encouragement. I
particularly appreciate their patience in answering my many questions and helping me to learn
new techniques. I would also like to thank all the wonderful people who made my time at the
University of Toronto a fun and rewarding experience.
My thesis was greatly enhanced through collaboration with William Crampton of the University
of Central Florida. I am extremely grateful for his help with equipment, recordings, and analysis
of EODs. His feedback and comments have always been prompt and constructive and his advice
is greatly appreciated.
My field work would not have been possible without a number of people who assisted me at
every step. Permit applications were facilitated in Panama by the Smithsonian Tropical Research
Institute (STRI), in Costa Rica by the Organization for Tropical Studies (OTS), and in Colombia
by the Instituto Alexander von Humboldt (IAvH). I would like to thank E. Bermingham and O.
Sanjur for supporting my trip to Panama. I am also indebted to the many people at STRI who
assisted me with specimens and field collections from both the Naos Island Laboratories and the
Bocas del Toro Research Station. I am also grateful to the many local fisherman and villagers
who assisted me in locating and catching electric fish. I would like to thank A. Summers, E.
Lewallen, and the students of the 2010 Marine Tropical Ecology Field Course for their role in
my first field collection experience. It will remain memorable for being both fun and successful.
I would like to extend a special thank you to Rigoberto Gonzalez at STRI who accompanied me
on many field collecting trips in Panama and who contributed greatly to making me feel at home
there. I would also like to thank Chielo for his resolute optimism and Kayla for her willingness to
accompany me on a collecting excursion on her vacation.
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I am very grateful to Francisco Campo and Ronald Vargas of OTS for their assistance in
organizing my trip to Costa Rica. Advice and collecting localities from William Bussing
(University of Costa Rica) proved invaluable and were very much appreciated. A special thank
you is owed to E. Lewallen for his field assistance on this trip and for helping to ensure that I
have fond memories of Costa Rica.
My trip to Colombia would not have been possible without the assistance of Javier Maldonado-
Ocampo. I am extremely grateful that he organized this trip and ensured that we were able to
collect the specimens that we needed. I would also like to thank D. Bloom, AO. Lara, and GC.
Rodriguez for their assistance in field collections. I would also like to thank them for helping to
make my time in Colombia very enjoyable.
This research was supported by a Natural Sciences and Engineering Research Council of Canada
(NSERC) Alexander Graham Bell Canada Graduate Scholarship (CGS) and Michael Smith
Foreign Study Supplement (MSFSS), a Fonds québécois de la recherche sur la nature et les
technologies (FQRNT) Bourse de maîtrise en recherche (B1), as well as a Sigma Xi (SX) Grant-
in-Aid of Research (GIAR) awarded to K. Brochu, in addition to an NSERC Discovery Grant to
NR. Lovejoy and an NSF Grant: NSF DEB-0614334 Evolution of Species and Signal Diversity
in the Neotropical Electric Fish Gymnotus (PI WGR. Crampton, CoPIS NR. Lovejoy, JS. Albert,
AA. Caputi). The University of Toronto also provided funds in the form of various Awards,
Grants, and TAships.
Above all, I would like to thank my family and friends for their support, encouragement, and
understanding while I continue to pursue my dream of studying amazing animals in
extraordinary places.
v
Table of Contents
Table of Contents
Abstract ........................................................................................................................................... ii
Acknowledgments .......................................................................................................................... iii
Table of Contents ............................................................................................................................ v
List of Tables ............................................................................................................................... viii
List of Figures ................................................................................................................................ ix
List of Abbreviations ..................................................................................................................... xi
List of Appendices ........................................................................................................................ xii
Chapter 1 Introduction .................................................................................................................... 1
1 Overview .................................................................................................................................... 1
2 Gymnotiform Biology and Phylogeny ....................................................................................... 2
3 Biology, phylogeny, and biogeography of Gymnotus ................................................................ 4
4 The Electrogenic and Electrosensory System (EES) ................................................................. 6
4.1 Electrogenesis ..................................................................................................................... 6
4.2 Pulse- vs. Wave-type Signals .............................................................................................. 8
4.3 Evolution of Multiphasic Signals...................................................................................... 10
5 Objectives, Hypotheses, and Predictions ................................................................................. 15
6 Significance .............................................................................................................................. 16
Chapter 2 Materials and Methods ................................................................................................. 17
1 Field Collection ........................................................................................................................ 17
2 Taxon Sampling ....................................................................................................................... 17
3 Molecular Phylogeny ............................................................................................................... 18
3.1 DNA Isolation, PCR, and Sequencing .............................................................................. 18
vi
3.2 Alignment ......................................................................................................................... 19
3.3 Phylogenetic Analysis ....................................................................................................... 20
4 Electric Waveform ................................................................................................................... 21
4.1 EOD Recordings ............................................................................................................... 21
4.2 EOD Character Evolution Analysis .................................................................................. 21
Chapter 3 Results .......................................................................................................................... 23
1 Molecular Dataset .................................................................................................................... 23
2 Phylogenetic Relationships ...................................................................................................... 23
2.1 Complete Dataset Analyses .............................................................................................. 23
2.2 Individual Gene Analyses ................................................................................................. 25
2.3 Molecular Sequence Divergence ...................................................................................... 26
3 EOD Evolution ......................................................................................................................... 27
3.1 Individual EOD Signals .................................................................................................... 27
3.2 Ancestral Character State Reconstruction ........................................................................ 27
Chapter 4 Discussion .................................................................................................................... 29
1 Gymnotus Phylogeny ............................................................................................................... 29
2 Biogeography of the trans-Andean species .............................................................................. 31
3 Electric Signal Evolution ......................................................................................................... 33
3.1 A Complicated History ..................................................................................................... 33
3.2 G. ardilai may be a recent introduction ............................................................................ 35
3.3 Mechanisms for a return to monophasy ............................................................................ 36
3.4 Adaptive significance of low-frequency energy ............................................................... 36
3.5 Cis-Andean Reductions in Phase Number ........................................................................ 41
3.6 Abiotic Selective Pressures ............................................................................................... 41
3.7 Corollaries ......................................................................................................................... 42
4 Future Directions ...................................................................................................................... 43
vii
5 Conclusions .............................................................................................................................. 44
References ..................................................................................................................................... 46
Appendices .................................................................................................................................... 81
viii
List of Tables
Table 1: List of specimens included in study.................................................................................54
Table 2: List of primers used for amplification and sequencing of the cyt b, 16S, RAG2, and Zic1
genes..............................................................................................................................................56
Table 3: Summary of EOD recordings..........................................................................................57
ix
List of Figures
Figure 1: Family level relationships of the order Gymnotiformes. Modified from Stoddard
(2002a)…………………………………………………………………………………………...59
Figure 2: Geographic distribution of gymnotiform species with delineation of biogeographic
regions. Modified from Albert et al. (2004)……………………………………………………...60
Figure 3: Type-locality map for 35 described Gymnotus species. Modified from Albert et al.
(2004)…………………………………………………………………………………………….61
Figure 4: Distribution Map for trans-Andean Gymnotus species………………………………..62
Figure 5: Morphological Hypothesis for Gymnotus after Albert et al. (2004)…………………..63
Figure 6: Molecular Hypothesis for Gymnotus after Lovejoy et al. (2010)...................................64
Figure 7: Electrostatic field of Gymnotiformes. Modified from Stoddard (2002a)……………...65
Figure 8: Spectral sensitivity of the two types of electroreceptor cells in Gymnotiformes.
Modified from Stoddard (2002a)………………………………………………………………...66
Figure 9: Pulse and Wave-type signal discharges after Stoddard and Markham (2008)………...67
Figure 10: Voltage-time waveforms of monophasic and multiphasic signals. Modified from
Stoddard (2002b)………………………………………………………………………………...68
Figure 11: Electric organ discharge production after Stoddard (2002a)…………………………69
Figure 12: Voltage/time waveform of both the first phase and the full EOD of Brachyhypopomus
pinnicaudatus and their corresponding power spectrum plotted over the spectral sensitivity of
ampullary electroreceptors. Modified from Stoddard (2002b)…………………………………..70
Figure 13: Collecting localities in Panama and Costa Rica……………………………………...71
Figure 14: Collecting localities in Colombia…………………………………………………….72
x
Figure 15: Strict consensus phylogeny of 422 most parsimonious trees showing Gymnotus
relationships, based on the combined analysis of cyt b, 16S, RAG2, and Zic1 genes (3807
characters, 5037 steps, CI=0.47, RI=0.85).....................................................................................73
Figure 16: Maximum Likelihood phylogeny showing Gymnotus relationships, based on the
combined analysis of mitochondrial (cyt b and 16S) and nuclear (RAG2 and Zic1) genes..........74
Figure 17: Bayesian phylogeny showing Gymnotus relationships, based on the combined analysis
of mitochondrial (cyt b and 16S) and nuclear (RAG2 and Zic1) genes........................................75
Figure 18: Results of Maximum Parsimony analyses of individual mtDNA and RAG2
datasets...........................................................................................................................................76
Figure 19: Results of Maximum Likelihood analysis of individual mtDNA, RAG2, and Zic1
datasets...........................................................................................................................................77
Figure 20: Electric organ discharges of five species of trans-Andean Gymnotus visualized as
voltage over time waveforms…………………………………………………………………….78
Figure 21: Maximum Likelihood Optimization of electric organ discharge (EOD) phase number
of Gymnotus species over the total evidence Maximum Likelihood phylogeny...........................79
Figure 22: Parsimony Optimization of electric organ discharge (EOD) phase number of
Gymnotus species over the total evidence Maximum Likelihood phylogeny…………………...80
xi
List of Abbreviations
16S – 16S ribosomal gene
CI – Consistency Index
cyt b – cytochrome b gene
EOD – electric organ discharge
ML – Maximum Likelihood
MP – Maximum Parsimony
mtDNA – mitochondrial DNA
mya – million years ago
RAG2 – recombinase activating gene-2
RI – Retention Index
Zic1 – zic family member-1 gene
xii
List of Appendices
Appendix A: 16S Alignment.........................................................................................................81
1
Chapter 1 Introduction
1 Overview
Fishes are one of the most diverse groups of vertebrates. They exhibit a variety of strategies in
their morphology, behaviour, and ecology. While marine environments account for the vast
majority of the available aquatic habitat, these environments only harbour about half of the
diversity. In contrast, freshwater environments, which comprise only a small percentage of the
available habitat, also contain about half of the diversity of fishes (Cohen 1970). This notable
discrepancy prompts questions regarding how speciation and diversification occur within
freshwater environments.
Freshwater fish are particularly diverse within the Neotropical region, where there are over 6,000
described species (Albert et al. 2004). The dynamic environment found in these regions, along
with high species richness makes these regions of intense interest. Our understanding of the
immense diversity of freshwater fishes is still in its infancy. This gap in our knowledge makes
Neotropical fishes especially appealing for studies of evolution and diversification.
Investigations into how this variation is generated and maintained are exceptionally important to
our appreciation and preservation of not only the Neotropical fauna, but of all freshwater fishes.
This is especially important in light of the many land use changes that are currently underway in
the Neotropics.
In this introduction, I begin with a consideration of general Gymnotiform biology and an
overview of the phylogenetics and biogeography of the group. Next, I examine these topics in
more detail with respect to the electric knifefish genus Gymnotus (Gymnotidae: Gymnotiformes).
Finally, I evaluate some of the hypotheses relating to the evolution of signal complexity in the
group. In the remainder of my thesis, I investigate the evolutionary history of Gymnotus, which
constitutes an important part of the Neotropical freshwater fish fauna. I present the results for
phylogenetic analyses of four genes using three different methods. I also test some predictions
arising from one particular hypothesis about the evolution of signal diversity. I consider signal
evolution in both a phylogenetic and biogeographic context. Finally, I examine the implications
2
arising from the analysis of electric signal evolution and provide some hypotheses for the
patterns that emerge.
2 Gymnotiform Biology and Phylogeny
The teleost order Gymnotiformes, the electric knifefishes, is a highly diverse group that is widely
distributed in the Neotropics. There are over 170 species within approximately 30 genera
distributed among five families. They are found in drainage basins from southern Mexico
(15°N), to northern Argentina (36°S), and also on the Caribbean island of Trinidad.
Gymnotiforms are found in many habitats and constitute an important component of the
Neotropical freshwater fish fauna (Lundberg et al. 1987, Crampton 1996, Albert 2000, Albert et
al. 2004, Albert and Crampton 2005a, Lovejoy et al. 2010).
Gymnotiforms are especially interesting due to their active electrogenic-electroreceptive system,
which allows them to sense electric fields and to generate electric signals using specialized
electric organs. Gymnotiforms generate a species-specific electric organ discharge (EOD), which
they use for electrolocation and electrocommunication (Lissman 1958, Stoddard 2002a, 2002b,
Albert et al. 2004, Lovejoy et al. 2010). These signals are stereotypical and quantifiable, and as a
result can assist in the identification of morphologically cryptic species. These signals allow
these fish to be active at night and exploit niches in dark sediment-rich rivers in the Neotropics.
Studies on this group offer an interesting perspective on the role of communication in mating
systems and species recognition (Albert et al. 2004, Lovejoy et al. 2010).
Most Gymnotiforms are nocturnal, which means that visual cues are generally less important.
Both the visual and olfactory systems in gymnotiforms are less developed than in most other
teleost fish. This reduction in senses probably occurred due to the extreme reliance of
gymnotiforms on the electrosensory system. In fact, gymnotiforms tend to have increased brain
size compared to other fish, due to a large amount of brain tissue specialized for interpreting
electric signals (Lissman 1958, Albert 2000, Crampton and Albert 2006). Due to the extreme
importance of this sensory modality in the evolution of the Gymnotiformes, most, if not all,
aspects of Gymnotiform ecology and biogeography are in some way related to the electric sense.
This phenomenon will be discussed in more detail below.
3
In one striking example of how the electrosensory system influences the biology of
gymnotiforms, the characteristic culteriform or knife-like body shape of all known gymnotiforms
actually optimizes the detection of electric fields along the body. This body shape is
accompanied by a long anal fin, which is used for locomotion. Gymnotiform fishes undulate the
anal fin allowing them to keep their body relatively straight while they swim both forwards and
backwards detecting fine scale difference in electric field variation (Lissman 1958, Albert 2000,
Nanjappa et al. 2000, Albert and Crampton 2005b).
The order Gymnotiformes has undergone rapid taxonomic change in the past 25 years, with
many new species being discovered, and many species limits being re-evaluated or redescribed
(Albert and Miller 1995, Campos-da-Paz 1996, Albert et al. 1999, Albert and Crampton 2003,
Crampton and Albert 2003, Crampton et al. 2003, 2005, Maldonado-Ocampo and Albert 2004,
Cox Fernandes et al. 2004, Fernandes et al. 2005, Cognato et al. 2007, Richer-de-Forges et al.
2009). There are likely even more species awaiting discovery among museum specimens and in
field collections from new locations (Albert and Crampton 2005a). It has also been suggested
that examination of chromosomes could lead to the discovery of even more cryptic species
differing in karyotypes (Milhomem et al. 2008).
The monophyly of Gymnotiformes is well-supported (Alves-Gomes et al. 1995, Alves-Gomes
1999, Albert 2000). Gymnotiformes are thought to be most closely related to the catfish order
Siluriformes (Fink and Fink 1981, Alves-Gomes et al. 1995), with which they share a system for
passively sensing electric fields; however, there is some disagreement about the relationships
between the Gymnotiformes, Siluriformes, and Characiformes, with several studies suggesting
alternate relationships (Dimmick and Larson 1996, Ortí and Meyer 1996, 1997, Saitoh et al.
2003, Lavoué et al. 2005, Peng et al. 2006, Li et al. 2008, Poulsen et al. 2009, Nakatani et al.
2011). Synapomorphies for Gymnotiformes include possession of an electrogenic system, a
culteriform body plan, subdermal eyes, lack of pelvic, dorsal, and adipose fins, and the ability to
regenerate a large portion of the caudal segment of their bodies (Alves-Gomes 1999, Albert
2000, Albert and Crampton 2005b).
Within the Gymnotiformes, the relationships are somewhat contentious. It has been suggested
that both Sternopygidae and Hypopomidae are paraphyletic (Alves-Gomes et al. 1995). The
monophyly of Gymnotidae, including Gymnotus and the monotypic Electrophorus electricus is
4
well-supported. Currently recognized family-level relationships are summarized in Figure 1.
Under this scheme, the family Gymnotidae represents the basal group, although Sternopygus has
been suggested to be the sister group to all other Gymnotiforms (Alves-Gomes et al. 1995,
Alves-Gomes 1999, Albert 2000).
Gymnotiforms are believed to have originated in South America about 100 million years ago at
approximately the time of separation of Africa and South America. No extant or fossil
Gymnotiforms are known from Africa. There are 11 fossil fragments from Bolivia that can be
ascribed to the Gymnotiformes; however, their placement on the phylogeny is ambiguous (Albert
and Fink 2007). Gymnotiforms diversified widely during the Tertiary and dispersed into a
variety of habitats from their inferred original habitat of small upland streams (Albert 2000,
Albert and Crampton 2005a). Gymnotiform lineages occur on both the eastern side of the Andes
(cis-Andean) and the western side (trans-Andean) (Figure 2), suggesting that considerable
lineage diversity was present before the uplift of the Andes mountains.
3 Biology, phylogeny, and biogeography of Gymnotus
Gymnotus, the banded electric knifefish, is the most diverse genus in the Gymnotiformes, with
35 known species, and several additional species awaiting description (Albert et al. 2004, Albert
and Crampton 2005a, Richer-de-Forges et al. 2009). Gymnotus is in the family Gymnotidae with
the monotypic Electrophorus electricus. Gymnotus is relatively ancient and is found across the
range of the gymnotiforms, with species on both the eastern side of the Andes (cis-Andean) and
the western side (trans-Andean) (Figure 3). Seven species are exclusively trans-Andean in
distribution (Figure 4) (Albert et al. 2004, Albert and Crampton 2005a, Lovejoy et al. 2010).
Gymnotus species are found in all major river drainages of South America and occupy a variety
of habitat types. They form one of the major components of the fauna found in floating meadows
composed of aquatic macrophytes. Most Gymnotus species inhabit only one habitat, but two
species (G. carapo and G. arapaima) have been found to be more generalist and inhabit multiple
habitat types (i.e. blackwater rivers, terra firme streams, and whitewater floodplains) (Crampton
1996, Albert 2000, Albert et al. 2004). All species are active nocturnally and eat invertebrates or
small fish. Adult males are often territorial and exhibit nest guarding behaviour in several species
(Albert 2000, Crampton and Hopkins 2005). Most Gymnotus species are also capable of aerial
5
respiration, using the gas bladder as an accessory air-breathing organ when oxygen is scarce
(Crampton 1998, Albert and Crampton 2005a).
Gymnotus species are generally characterized as having alternating light and dark pigment bands,
hence the common name, banded electric knifefish. Since most Gymnotus are nocturnal, the
bands are likely not used for mating or social communication. Alternately, they have been
suggested to aid in avoidance of visual predation by disrupting visual recognition (Albert et al.
2004); however, there are some species that do not exhibit this colour pattern. In particular, all
the trans-Andean species are characterized by the breakdown of this trait to varying degrees.
Gymnotus cylindricus and Gymnotus maculosus have small spots of varying sizes on their body
(Albert and Miller 1995, Campos-da-Paz 1996). Gymnotus esmeraldas possesses a patchy
pattern of pale blotches along the majority of the anterior portion of the body with some banding
on the posterior portion of the body (Albert and Crampton 2003). Gymnotus henni and Gymnotus
choco show some breakdown of this banding pattern on the posterior portion of their bodies,
where the bands are irregular and wavy (Albert and Crampton 2003). Gymnotus ardilai exhibits
a loss of the banding pattern with increasing size (Maldonado-Ocampo and Albert 2004). If the
pigmentation bands do function as cryptic colouration, the trans-Andean species may have lost
this trait due to a reduction in predation pressure selecting for that character.
Due to the relatively high number of species, wide distribution, and great variation in character
traits, Gymnotus is a good group to answer questions about the evolution of diversity in the
Neotropics. However, in order to test hypotheses about diversification, it is necessary to have a
good phylogenetic framework so that this work can be placed in an evolutionary context.
Gymnotus species diversity has substantially increased in the past several years as the group has
been revised and new species have been added. The most comprehensive previous phylogenies
completed include Albert et al. (2004) which was based on morphology, as well as a molecular
analysis by Lovejoy et al. (2010) (Figure 5 and 6, respectively). Albert et al. (2004) proposed
three species groups, based on the major clades in their phylogenetic hypothesis: the G.
cylindricus group, the G. carapo group, and the G. pantherinus group. The G. cylindricus group,
composed of the two Middle American species G. cylindricus and G. maculosus, was suggested
to form a basal clade that is the sister clade to all the species of South America. Both their G.
pantherinus group and their G carapo group were monophyletic and contained species from both
6
sides of the Andes; however, support for the G. pantherinus group was weak. This phylogeny
suggested that the trans-Andean species are distributed in multiple clades; however, this has
never been tested rigorously with molecular evidence.
The phylogenetic hypothesis proposed by Lovejoy et al. (2010) was based on morphological
characters following Albert et al. (2004), as well as three genes, two mitochondrial (cyt b and
16S) and one nuclear (RAG2). Lovejoy et al. (2010) proposed five lineages based on the major
clades of their phylogeny: the G. carapo group (eight species), the G1 clade (five species), the
G2 clade (three species), G. pantherinus, and G. cylindricus. In all analyses except the
morphological one, the G2 clade was found to be the sister group to all other species, and G.
cylindricus was found to be the sister taxa to the G. carapo group. This phylogeny suggests that
the Middle American species are not found at the base of the phylogeny but are nested within
Gymnotus. This has important implications for reconstructions of both historical biogeography
and character evolution. This phylogenetic analysis did not test the hypothesis that the trans-
Andean species are distributed in multiple clades, as only one (G. cylindricus) of the seven
known trans-Andean species was included.
A major goal of this study is to clarify the phylogenetic position of trans-Andean lineages within
Gymnotus. This insight will provide valuable biogeographic information regarding the effects of
the Andes on Neotropical diversification. A new phylogenetic hypothesis will also be critical to
comparative studies of character evolution because it will allow the state changes to be viewed
within the context of evolutionary history, as well as provide some information regarding the
relative timing of the state changes (Alves-Gomes 1999). Finally, understanding the phylogeny
of trans-Andean lineages will allow a test of the Predator Avoidance Hypothesis for the
evolution of electric signals, as described below.
4 The Electrogenic and Electrosensory System (EES)
4.1 Electrogenesis
Electric signals are intimately linked with many aspects of Gymnotiform biology. They directly
impact fitness in this group and are influenced by several selective pressures related to the dual
functions of electrolocation and electrocommunication. Adaptations for one function can
seriously affect the other. Electric signals are also influenced by the physical constraints of the
7
environment on signal conduction and detection, as well as the physiological constraints of the
fish to produce and detect these signals. It is no surprise, therefore, that the evolution of electric
signals is a key factor contributing to diversification and habitat specialization (Stoddard 2002a,
Albert and Crampton 2005a).
While the capacity to sense electric signals has evolved in multiple groups of aquatic animals
(e.g. monotremes, elasmobranchs, and catfishes) (Hanika and Kramer 1999, 2000, Montgomery
and Bodznick 1999, Pettigrew 1999, Albert and Crampton 2005b), active electrogenesis has
evolved only a few independent times, including in the Neotropical order Gymnotiformes, the
African superfamily Mormyroidae, and some species within two families of African catfish in
the order Siluriformes (Stoddard 2002a).
All gymnotiforms except the electric eel emit only weakly electric discharges of generally less
than 100mV (Crampton and Albert 2006). The electric eel generally emits a discharge of
approximately 10mV for communication and navigation, but can emit a discharge of up to 600V
for prey capture or defence (Crampton and Albert 2006). While most gymnotiforms always emit
their signal, some species have been known to switch off their EOD when startled or exposed to
novel stimuli, which may have evolved as a mechanism to evade electroreceptive predators or to
avoid undesirable males (Curtis and Stoddard 2003, Crampton and Albert 2006); however, this
would allow only a brief respite.
Gymnotiformes possess a specialized electric organ that extends along the ventral portion of the
body from just behind the head to the tail. This specialized electric organ contains electrocytes,
which are cells specialized for generating an electric field around the body of the fish. When an
object enters the field, it distorts the wave in a stereotypical fashion depending on its resistance
and capacitance and allows the fish to discern a large amount of information about the object
(Figure 7). The fish are able to tell the size, shape, and material of an inanimate object, and can
also discern whether it‟s sensing a conspecific, potential mate, or potential predator. A 10-20cm
fish can communication within approximately 1 m from its body (Hopkins 1999, Stoddard
2002a). The distance for electrocommunication is greater than the distance for electrolocation
(Knudsen 1975, Albert and Crampton 2005b). The electroreceptor cells work in tandem with the
electric organ to detect changes in the fish‟s individual waveform, as well as the electric organ
discharges of other electric fish (Alves-Gomes 2001, Crampton and Albert 2006). Gymnotiforms
8
possess two types of electroreceptive cells: ampullary and tuberous (Figure 8). Ampullary
electroreceptors are used in passive electroreception and are tuned to low-frequency energy (~0-
100Hz). Tuberous electroreceptors are tuned to higher frequency energy (~100-3,000Hz)
(Hopkins 1974, Stoddard 1999, 2002a). Stoddard (2002a) suggested that tuberous
electroreceptors evolved for electrolocation. Tuberous electroreceptors tend to have a narrow
tuning range and greater sensitivity to the fish‟s own EOD than to those of conspecifics. If these
electroreceptors evolved for communication, they would be expected to be tuned to a much
broader range and be more sensitive to the signals of other fish.
4.2 Pulse- vs. Wave-type Signals
There are two main physiological types of electric signals (Figure 9). Pulse-type signals are
characterized by one to six phases (i.e. deviations from the 0V baseline) of alternating polarity
punctuated by brief periods of silence. In contrast, wave-type signals are characterized by a
pattern of one to four phases recurring in a continuous cycle (Albert 2000, Albert and Crampton
2005a). Pulse species tend to exhibit a broader range of physical and physiological states,
allowing them to navigate and communicate in a variety of conditions. They are also prone to
electrical interference and are especially vulnerable to predation by electroreceptive predators, as
discussed below. Wave species are restricted to a much narrower range of environmental
conditions due to constraints imposed on them by their consistent and continuous discharge.
They are, however, less affected by electrical interference and seem to sustain their EOD at such
frequencies as to be much less conspicuous to electroreceptive predators (Stoddard 2002a).
Both pulse-type and wave-type EOD signals can vary in phase number and polarity, as well as in
duration and amplitude for each phase (Stoddard et al. 2006). Both pulse-type and wave-type
species have evolved specialized physiology and habits to adapt to their environment (Stoddard
2002a). Hopkins and Heiligenberg (1978) proposed that wave-type species evolved due to the
need for greater temporal resolution. Fast flowing, well-oxygenated environments require a
higher and more stable EOD discharge rate in order to effectively navigate and capture prey in
such a dynamic environment. Wave-type species that are found in fast flowing habitats have
higher repetition rates of their EOD than wave-types species found in slower flowing habitats.
Even pulse-type gymnotiforms in fast flowing environments tend to have more regular EOD
rates and smaller changes between the day-night pulse rates. Increased rate of EOD discharge
9
provides a greater temporal acuity. Fast flowing environments tend to be highly dynamic and
change rapidly with time, demanding high temporal acuity from a fish foraging in that
environment. Prey items that are highly mobile might also demand a foraging fish to have high
temporal acuity (Crampton and Albert 2006).
The high dissolved oxygen content in fast flowing habitats is particularly important because of
the energetic considerations of EOD generation (Crampton 1998, Crampton and Albert 2006).
Species with wave-type signals swim continuously, cannot modulate their EOD rate, and
generally emit signals at a higher rate than pulse-type species. These differences could indicate
that wave-type species have higher energetic requirements and therefore require well-oxygenated
waters. Oxygen consumption in both pulse- and wave-type species was found to be similar;
however, “scan swimming” (a foraging behaviour where the fish swims forwards and backwards
to scan the environment) has been shown to drastically increase the oxygen consumption
compared to resting. Scan swimming is not observed in pulse-type gymnotiforms; therefore it
could represent an additional energy cost to wave-type fish which may restrict them to well-
oxygenated waters (Julian et al. 2003, Albert and Crampton 2005b). In fact, wave-type species
have no physiological adaptations to deal with hypoxia and are generally restricted to well-
oxygenated waters. Pulse-types are dominant in hypoxic water, but are also dominant in some
well-oxygenated environments, such as terra firme streams (Crampton 1998, Julian et al. 2003,
Albert and Crampton 2005b, Crampton and Albert 2006). It has been suggested that they occupy
microhabitats with slower flow rates, where they are not subject to the fast flowing waters of the
main river channel (Albert and Crampton 2005b).
Changes in temperature are also important because they affect the speed of physiological
processes, which is reflected in longer or shorter EODs (Crampton and Albert 2006). Wave-type
species seem to require a temperature of 26°C ± 3-4°C, with most occurring in the exceptionally
thermostable environments of deep river channels. When temperatures change they induce
changes in the frequency of the EOD; however the electroreceptors do not become tuned to the
new frequency as rapidly as the temperature changes. When the environmental temperature
changes by more than 3 or 4°C the tuberous electroreceptors of wave-type species may no longer
be capable of sensing their own EOD due to the mismatch in the frequencies (Stoddard 2002b,
Albert and Crampton 2005b). Brachyhypopomus pinnicaudatus has been found to drastically
10
reduce the second phase of the EOD in response to high temperatures, possibly in relation to
cues that indicate the onset of the breeding season (Silva et al. 1999).
In contrast to wave-type species, pulse-type species have a higher spatial resolution due to their
wider range of frequencies that allows them to detect a wider range of capacitances from natural
objects that enter their electric field (Crampton and Albert 2006). This adaptation gives pulse-
type species an advantage in spatially complex environments, such as plant root masses;
however, pulse-type species are generally more restricted to high conductivity ecosystems
(Hopkins 1999, Crampton and Albert 2006).
Conductivity is important due to its correlation with primary productivity and pH. It is also
correlated to how easy it is to propagate the electric signal (Albert and Crampton 2005a,
Crampton and Albert 2006). The higher the conductivity, the less external resistance is
encountered by the electric current of the EOD. Aquatic ecosystems can be divided into low
conductivity (5-60µScm-1
) and high conductivity (60-700+µScm-1
) waters. In gymnotiforms,
some characteristic morphological adaptations are associated with changes in conductivity.
Species in low conductivity environments tend to have long, thin tails, representing more
electrocytes in series, whereas species in high conductivity environments tend to have short,
thick tails, representing more electrocytes in parallel. Electrocytes in series maximize the power
of an EOD where external resistance is high, i.e. low conductivity environments. Conversely,
electrocytes in parallel maximize the power of an EOD where external resistance is low, i.e. high
conductivity environments (Hopkins 1999).
4.3 Evolution of Multiphasic Signals
This thesis is primarily concerned with the evolution of the pulse-type signals in Gymnotus. One
of the most obvious differences among pulse-type signals of different species is the number of
phases. Monophasic signals are composed of one phase, while multiphasic signals are composed
of two to six phases (Figure 10). The arrangement of electrocytes and accessory electric organs
are important in determining phase number (Figure 11) (Hopkins 1988, Stoddard 2002a). The
plesiomorphic signal state in Gymnotiforms is thought to be the monophasic pulse-type
(Stoddard 1999, 2002a, 2002b, Alves-Gomes 2001, Albert and Crampton 2005a). The basal
family, Gymnotidae (comprised of Gymnotus and Electrophorus), exhibits pulse-type signals
(Crampton and Albert 2006) and E. electricus, the sister lineage to Gymnotus, has a monophasic
11
EOD. Additionally, all larval gymnotiforms examined exhibit monophasic or quasi-monophasic
signals with an ontogenetic development of the multiphasic signals (Stoddard 2002b, Lovejoy et
al. 2010, Crampton et al. 2011). The electric organ of all pulse-type gymnotiforms is derived
from hypaxial muscle. This electric organ remains the same throughout development in pulse-
type gymnotiforms, while the electric organ of wave-type species is replaced by a myogenic or
neurogenic adult electric organ early in their ontogeny (Albert and Crampton 2005b, Pereira et
al. 2007). In Gymnotus, the multiphasic signal usually develops when individuals reach a size
over 25mm, typically after a period of several weeks (Crampton and Hopkins 2005, Pereira et al.
2007, Kirschbaum and Schwassmann 2008). Based on these combined lines of evidence, the
monophasic pulse-type signal is considered to be plesiomorphic in Gymnotiformes (Stoddard
1999, 2002a, 2002b, Alves-Gomes 2001, Albert and Crampton 2005a).
Stoddard (1999, 2002a, 2002b) considered several hypotheses to explain why multiphasic signals
might have evolved from a monophasic ancestral condition. First, he considered that multiphasic
signals might provide an advantage in electrolocation. Most electric fish have a high density of
electroreceptors on their head, therefore this should be the area where these fish have the highest
sensory acuity, and indeed, some electric fish have been observed to explore new environments
and forage exclusively with their heads (Nanjappa et al. 2000). This evidence would suggest that
if multiphasic signals evolved to support electrolocation functions, the localized electric field
around the head of the electric fish should exhibit a multiphasic waveform. The electric organ
discharge can vary spatially and temporally in the localized area surrounding the fish. Due to the
physiology of the electric organ, several genera, Brachyhypopomus, Rhamphichthys, and
Gymnotus, are known to lack the second phase of the EOD at their heads. Increased signal
complexity at the tail end of the fish, where electrolocation is less critical, would suggest that
multiphasic signals did not evolve to enhance electrolocation. This hypothesis could be better
tested in a laboratory experiment with the foraging ability of both monophasic and multiphasic
individuals evaluated in complex vs. simple habitat types and with moving vs. stationary prey.
Multiphasic signals are sexually dimorphic in some groups of electric fish (Stoddard 2002b,
Albert and Crampton 2005a), which could indicate that they evolved to aid in mate attraction or
mate competition. Stoddard (2002b) suggests that if multiphasic signals evolved for sexual
selection then either only the displaying sex should have evolved additional phases, or if both
species evolved additional phases, they should have always been sexually dimorphic. In
12
multiphasic species, both sexes exhibit the same number of phases and do not always exhibit
sexual dimorphism (Curtis and Stoddard 2003, Crampton and Albert 2006). If sexual selection
was the main force driving evolution of multiphasic signals, then sexual dimorphism should be
present throughout multiphasic lineages. This pattern is not observed in any of the pulse-type
families (Stoddard 2002b). In light of this evidence, Stoddard (2002b) concluded that it is
unlikely that multiphasic signals evolved to enhance sexual signalling, although it does appear
that additional phases have secondarily been adapted for that purpose in several groups,
promoting further diversification.
EODs have also been suggested to play a role in species recognition (Hopkins and Bass 1981,
Hopkins 1999, Albert 2000, Crampton and Albert 2006). A larger number of phases increases
signal complexity, providing more parameters that can potentially be differentiated to increase
the distinction between species. If multiphasic signals evolved to facilitate reproductive isolation,
all phases would be expected to exhibit a high degree of differentiation and in particular, the
second phase would be expected to exhibit a large degree of interspecific differentiation. In the
gymnotiform Brachyhypopomus and the mormyrid Brienomyrus the first phase exhibits more
interspecific variation, while the other phases exhibit more intraspecific variation (Stoddard
2002a, 2002b). This evidence suggests that it is unlikely that multiphasic signals evolved to
improve species recognition; however, reproductive isolation does likely drive diversification
and complexity within the group.
Many species of gymnotiforms are territorial; therefore any adaptation that could increase
territory size would help to increase fitness (Knudsen 1975, Stoddard 2002b). In electric fish,
greater signal amplitude allows the signal to be broadcast further, effectively increasing signal
space. An extra phase in the electric signal would theoretically increase the amplitude without
any additional power output, so territorial species would be expected to be more likely to have
multiphasic signals than non-territorial species. Unfortunately, comparisons of territorial
behaviour are not available for most species, much less between closely related monophasic and
multiphasic species. Alternately, Stoddard (2002b) suggested that if multiphasic signals evolved
to improve territory defence by increasing the signal amplitude, then multiphasic signals should
exhibit greater amplitude than monophasic species. In the genus Brachyhypopomus, the
monophasic species has far greater signal amplitude than its multiphasic congeners (Stoddard
2002a, 2002b). Additionally, all strongly electric fish possess monophasic EODs with high
13
amplitude. One species of mormyrid in the genus Hyppopotamyrus has been found to have a
very low amplitude monophasic EOD (Hanika and Kramer 2000); however, the genus is
relatively nested in the mormyrid lineage and therefore its monophasy is likely a derived
condition and cannot be considered as homologous to the ancestral monophasic condition
(Stoddard 2002b). Therefore, Stoddard (2002b) concluded that he found no evidence to support
territory defence as the selective pressure driving the evolution of multiphasic signals although
he did concede that the evidence against this hypothesis is largely based on comparisons of EOD
amplitude instead of territorial behaviour and thus could be much stronger.
The Predator Avoidance Hypothesis proposes that multiphasic signals evolved to provide crypsis
from electroreceptive predators. Gymnotiforms have probably always had electroreceptive
predators, considering that their sister group, the Siluriformes (catfishes), possess a system for
sensing electric fields. Many important predators that occupy the same habitats as gymnotiforms
(including freshwater rays, catfishes, and other gymnotiforms) possess ampullary
electroreceptors that allow them to detect electric signals. If multiphasic signals evolved to be
cryptic to electroreceptive predators, then multiphasic signals should be less detectable to
electroreceptive predators. Ampullary electroreceptors are sensitive to low-frequency energy in a
range of approximately 0-100Hz, with a maximum sensitivity at approximately 30Hz for
gymnotiforms and 8Hz for catfish (Hanika and Kramer 1999, 2000, Stoddard 1999, 2002a). The
amount of low-frequency energy in an EOD is a function of the amount of asymmetry in the
voltage-time waveform. Signals that have equal amounts of energy above and below 0V cancel
out the low-frequency DC component of their signal and therefore have a reduced amount of
energy in the low-frequency range. Signals that have an asymmetric distribution of energy above
and below 0V tend to have an increased low-frequency component to their EOD. Monophasic
signals possess no energy below 0V, representing the asymmetrical extreme. Monophasic signals
have a large low-frequency component to their signal, which falls well within the range of
ampullary electroreceptors. Multiphasic signals tend to emit much higher frequency energy,
which can be detected by tuberous electroreceptors possessed by gymnotiforms but not catfish,
while being relatively cryptic to ampullary electroreceptors (Figure 12). This evidence supports
the proposal of the Predator Avoidance Hypothesis for the evolution of multiphasic signals,
which suggests that multiphasic waveforms evolved as a mechanism to avoid electroreceptive
predators (Stoddard 1999, 2002a, 2002b).
14
Stoddard (1999) tested whether multiphasic signals provide crypsis by training an electric eel to
respond to electric playback signals and then presenting it randomly with either a biphasic signal
or a monophasic signal (the same biphasic signal with the second phase digitally deleted). The
eel was much more likely to approach the monophasic signal than the biphasic signal. These
results imply that a monophasic signal may be more likely to elicit a predation attempt.
Multiphasic signals appear to be less detectable by the electric eel, suggesting that a multiphasic
species would be more adept at evading predation attempts. Hanika and Kramer (1999, 2000)
also found similar results studying the catfish Clarias gariepinus and the mormyrid Marcusenius
macrolepidotus. C. gariepinus was found to prey almost exclusively on males of M.
macrolepidotus. Playback experiments determined that catfish could always detect the signals of
males, but never of females. Males of M. macrolepidotus increase the duration of their EODs
upon maturation, increasing the low-frequency energy content of those signals. This change in
EOD parameter tends to attract more females, but also more predators. They also tested several
other species of mormyrids and found that species with a monophasic, or quasi-monophasic
discharge were also easily detected by C. gariepinus. These results provide additional support for
the idea that low-frequency energy is easily detectable by ampullary electroreceptors and that
this predation pressure is a strong force selecting for crypsis in electric fish.
Stoddard (1999, 2002a, 2002b) also proposed biogeographic support for the Predator Avoidance
Hypothesis. Electric eels are not present in the trans-Andean region, and both freshwater rays
and pimelodid catfish, which represent key electroreceptive predator groups, exhibit reduced
abundance and diversity in this region (Miller 1966). Species that are exclusively trans-Andean
in distribution may therefore experience reduced predation pressure. The Predator Avoidance
Hypothesis predicts that in areas of low predation, species would retain the ancestral monophasic
condition. The only trans-Andean Gymnotus species to have their EOD examined (G. cylindricus
and G. maculosus) show monophasic EODs. In contrast all adult pulse-type gymnotiform species
examined to date in cis-Andean habitats, where predation by electroreceptive predators is
expected to be high, exhibit multiphasic waveforms, except for one Brachyhypopomus species,
which may be a Batesian mimic of the electric eel, and the electric eel itself (Stoddard 1999,
Lovejoy et al. 2010). This evidence is in line with the Predator Avoidance Hypothesis and
supports the idea that predation pressure drove the evolution of multiphasic signals. These
patterns indicate that the monophasic Gymnotus species retained the ancestral monophasic
15
condition due to a lack of predation pressure selecting for crypsis, while cis-Andean groups
evolved multiphasic signals to evade electroreceptive predators.
The obvious geographic patterns predicted by the Predator Avoidance Hypothesis in Gymnotus,
make it an ideal group in which to test these ideas. Following this line of evidence, the
phylogeny of Lovejoy et al. (2010) examined the evolution of EOD phase number, including the
evidence that all adult cis-Andean Gymnotus species with a known EOD exhibit multiphasic
signals, while two trans-Andean species show monophasic discharges (G. cylindricus and G.
maculosus). This study was only able to include one trans-Andean species (G. cylindricus),
which did not contribute findings on the signal evolution of trans-Andean species. The available
evidence provides some support for the Predator Avoidance Hypothesis; however, this theory
would have more robust support in Gymnotus if more trans-Andean species are examined.
Although multiple hypotheses have been proposed to explain the evolution of multiphasic
signals, an evaluation of all of these is outside the scope of this thesis. Since the Predator
Avoidance Hypothesis has traditionally been considered to be the best explanation of multiphasic
signal evolution, with multiple lines of supporting evidence, and testable predictions, my thesis
will focus on the evaluation of this hypothesis within the genus Gymnotus. In order to evaluate
the Predator Avoidance Hypothesis, I will collect EOD signal recordings from trans-Andean
Gymnotus species and explore EOD evolution in a phylogenetic context.
5 Objectives, Hypotheses, and Predictions
The first objective of this thesis is to propose a new phylogenetic hypothesis for Gymnotus, using
additional genes and species that were not included in previous datasets. This phylogeny will be
used to evaluate previous phylogenies proposed by Albert et al. (2004) and Lovejoy et al. (2010).
It will also be used to determine the phylogenetic position of the trans-Andean Gymnotus
species. I will explicitly test the hypotheses that (1) trans-Andean species do not constitute a
monophyletic group, and are distributed in multiple clades, as proposed by Albert et al. (2004),
and (2) that the trans-Andean G. cylindricus lineage is not the sister group to all other Gymnotus
species, as proposed by Lovejoy et al. (2010).
The second objective of this thesis is to test the hypothesis that trans-Andean Gymnotus species
exhibit monophasic EODs, as predicted by the Predator Avoidance Hypothesis. To do this,
16
EODs from trans-Andean Gymnotus species will be recorded in the field and used to determine
EOD phase number. The evolution of EOD phase number will also be considered in a
phylogenetic context, to test the prediction that trans-Andean lineages should show evolution of
monophasic EODs. If multiple independent lineages of trans-Andean fauna are recovered in the
phylogeny, it will provide more independent tests for this prediction.
6 Significance
Understanding the phylogeny of Gymnotus will provide valuable information concerning
Neotropical speciation and biogeography. This study will be the first to include six of the seven
trans-Andean species of Gymnotus in a molecular phylogenetic analysis and will represent the
most complete phylogenetic hypothesis generated to date for the genus. My work will provide
new information on EOD waveforms for the trans-Andean fauna, as well as an analysis of the
evolution of phase number. My results will help to clarify the evolution of electric fish
communication signals and evaluate the relevance of the Predator Avoidance Hypothesis for
Gymnotus. Results from my thesis will provide the groundwork for further studies on Gymnotus,
such as the variation and evolution of other aspects of EOD parameters, and corresponding
implications for species recognition and mate choice.
17
Chapter 2 Materials and Methods
1 Field Collection
Field collection expeditions to three countries were undertaken to collect various species of
trans-Andean Gymnotus. The first trip was to Panama from February-May 2010, with the
assistance of the Smithsonian Tropical Research Institute (STRI). An additional trip to Costa
Rica was carried out for two weeks in April 2010 with the assistance of the Organization for
Tropical Studies. A map of Panamanian and Costa Rican collecting localities is shown in Figure
13. A collecting trip was organized to Colombia in June 2010. A map of Colombian collecting
localities is shown in Figure 14.
Specimens were located in the field by the authors and colleagues using an electric fish detector,
which consists of a differential amplifier and speaker connected to electrodes that are placed on
the end of a pole and submerged in the water (Wells and Crampton 2006, Crampton et al. 2007).
Specimens were then collected using dipnets with 3-4 mm mesh size. Fish were kept individually
in aerated buckets in the field for EOD recording procedures. Subsequently, they were
euthanized according to animal care protocols. Muscle tissue was then sampled and stored in 95-
100% ethanol. Specimens were preserved using 10% formaldehyde and then transferred into
70% ethanol for permanent storage. Vouchers have been deposited in museum collections (See
Table 1 for voucher numbers).
2 Taxon Sampling
A total of 35 Gymnotus species were included in this analysis, comprising 22 cis-Andean species
and six trans-Andean species out of the 35 described species, along with an additional seven cis-
Andean species that have not yet been formally identified. Two individuals were sequenced for
each species whenever possible. More individuals were sequenced across the range of those
species with an extensive distribution (G. coropinae and G. carapo) to consider any geographic
variation. Eight additional taxa were selected from among the gymnotiform families, including
Gymnotidae (Electrophorus), Rhamphichthyidae (Rhamphichthys), Hypopomidae (Hypopomus,
Brachyhypopomus), and Sternopygidae (Sternopygus). Sternopygus macrurus and S. astrabes
were used as the outgroup taxa. A total of 97 individuals were analyzed, including 95 ingroup
18
individuals and 2 outgroup individuals. Table 1 provides a complete list of specimens included in
this study.
3 Molecular Phylogeny
3.1 DNA Isolation, PCR, and Sequencing
Existing sequences were available for cyt b, 16S, and RAG2 for 27 cis-Andean and one trans-
Andean Gymnotus species, as well as the eight outgroup species (Lovejoy et al. 2010). Here I
added two cis-Andean species and five trans-Andean species, as well as the new gene Zic1.
DNA was extracted from muscle tissue using DNeasy Blood and Tissue Kits (QIAGEN). The
polymerase chain reaction (PCR) was used to amplify fragments of two nuclear genes and two
mitochondrial (mtDNA) genes using various combinations of primers (Primer sequences are
listed in Table 2). The nuclear gene fragments include 840 bp of the zic family member 1 gene
(Zic1), and 1295 bp of the recombinase activating gene-2 (RAG2). The mtDNA genes include
1126 bp of cytochrome b gene (cyt b), and 546 bp of the 16S ribosomal gene (16S). These genes
were selected based on their successful use in several taxa, particularly within the
Gymnotiformes, and represent a selection of both faster- and slower-evolving genes from the
mitochondrial and nuclear genomes (Palumbi et al. 1991, Meyer 1993, Palumbi 1996, Lovejoy
and Collette 2001, Li et al. 2007, Lovejoy et al. 2010, Maldonado-Ocampo 2011). Cytochrome b
exhibits variable rates of evolution across sites, with some regions being highly conserved, most
likely due to their importance in the function of the protein in the electron transport chain
(Palumbi 1996). 16S seems to be relatively conserved in some regions and hypervariable in
others, although it has been suggested to evolve more slowly compared to other genes in the
mitochondrial genome (Palumbi 1996). RAG2 evolves more slowly than mitochondrial genes
and is known to exhibit less homoplasy (Lovejoy and Collette 2001). The three genes where
existing sequences were available have been shown to provide good phylogenetic resolution in
gymnotiforms (Lovejoy et al. 2010). Zic1 was found to be a useful nuclear gene marker in a
study of 36 taxa of ray-finned fishes because it possesses a long, uninterrupted exon that is
relatively well-conserved (Li et al. 2007). It was also used with success in Sternopygidae,
another family of Gymnotiformes (Maldonado-Ocampo 2011). Using a diverse set of genes
assists in avoiding problems of systematic bias, such as nucleotide compositional bias (where
lineages with greater similarity in their nucleotide composition are grouped together, regardless
19
of their evolutionary history), long-branch attraction (when rapidly evolving lineages are
grouped together due to the accumulation of changes, regardless of their evolutionary history),
and heterotachy (changes in rates of substitution over time) (Li et al. 2007).
PCR reactions for cyt b, 16S, and RAG2 were carried out in 25µl amounts using 2.5µl 10x Taq
Buffer with (NH4)2SO4, 2µl of a 10µM mixture of each dNTP, 1.5µl of 25µM MgCl2, 1µl of 10
µM of each primer, 0.2µl of 1 U of Taq DNA Polymerase, and 2 µl of DNA. PCR reactions for
Zic1 were carried out in 25µl amounts using 2.5µl 10x Taq Buffer with (NH4)2SO4, 2µl of a
10µM mixture of each dNTP, 3µl of 25µM MgCl2, 1µl of 10 µM of each primer, 0.5µl of 1 U of
Taq DNA Polymerase, and 2µl of DNA.
Thermocycler conditions for cyt b, 16S, and Zic1 were: 95°C for 30s denaturation; 48-50°C (cyt
b), 54-58°C (16S), or 52°C (Zic1) for 60s annealing; and 72°C for 60s (16S), or 90s (cyt b, Zic1)
extension. This protocol was repeated for 35-38 (cyt b, 16S), or 40 (Zic1) cycles with hold steps
of 95°C for 30s (cyt b), 60s (16S), or 150s (Zic1) before the first cycle and 72°C for 300s after
the final cycle. Thermocycler conditions for RAG2 followed a touchdown protocol: 95°C for 30s
denaturation, 58°C, 56°C, 54°C, 52°C, (or 56°C, 54°C, 52°C, 50°C) for two cycles each, then
50°C (or 48°C) for 32 cycles annealing for 60s, and 72°C for 90s extension.
PCR products were purified using QIAQuick PCR Purification Kits (QIAGEN). Sequencing was
conducted at the DNA Sequencing Facility at the Toronto Sick Kids Hospital. Sequencing was
conducted using external primers, with one additional set of internal primers, Zic1_intF and
Zic1_intR, designed for this study using a preliminary Zic1 alignment.
3.2 Alignment
Sequences were edited and visually aligned using Sequencher 4.6 (Gene Codes Corp.). No
insertions or deletions were observed in cyt b or Zic1. A one codon indel was observed in one
RAG2 sequence. The final alignment for 16S followed Lovejoy et al. (2010). Regions of the
alignment surrounding indels where homology could not be determined were considered to be
ambiguous. Ambiguous regions were then excluded from the analyses. Ambiguity in RAG2
consisted only of four base positions surrounding the one indel. Ambiguity in 16S consisted of
several regions. The alignment for 16S can be viewed in Appendix A.
20
3.3 Phylogenetic Analysis
Nuclear and mitochondrial data were combined into a total evidence dataset using Geneious
(Drummond et al. 2011) consisting of 3807 characters for 97 OTUs. Data partitions were defined
as nuclear (RAG2 and Zic1) and mtDNA (cyt b and 16S). Analyses were conducted separately
for each nuclear gene, the mtDNA dataset, and the total evidence dataset.
Parsimony analyses were conducted in PAUP* (Swofford 2002). Sternopygus macrurus and S.
astrabes were used as the outgroup taxa. Gaps were treated as missing data. I used the following
parameters for all parsimony analyses: heuristic search algorithm, 1000 random-addition
sequence replicates, and TBR branch swapping. Bootstrap values (Felsenstein 1985) were also
calculated using the heuristic search algorithm with 1000 bootstrap replicates and 10 random-
addition sequence replicates.
Maximum Likelihood analysis (Guindon and Gascuel 2003) was performed using RAxML 7.2.8
(Stamatakis 2006, Stamatakis et al. 2008) with default parameters under the GTR+G model. I
used jModeltest (Guindon and Gascuel 2003, Posada 2008) to select models based on the
Corrected Akaike Information Criterion (AICc) and Bayesian Information Criterion (BIC). The
best fitting model for the total evidence dataset, according to both AICc and BIC, was TIM2+G;
however, the differences in AICc and BIC scores between this model and the GTR+G model
were small and the GTR+G model was calculated to have a higher likelihood, therefore, I opted
to use the GTR+G model.
Bayesian analysis was implemented in MrBayes 3.1.2 (Ronquist and Huelsenbeck 2003). All
partitions were unlinked. Two runs were performed, composed of four Markov Chains, with a
heating value of 0.065. Markov Chains were run for 20 million generations, sampling every 1000
generations. I assessed convergence by several methods. The average standard deviation of split
frequencies was 0.012 in MrBayes. The potential scale reduction factor (PSRF), which is a
convergence diagnostic for branch length posterior probabilities, approached one as the runs
converged (Gelman and Rubin 1992). Log-likelihood scores and other parameters were also
plotted in Tracer 1.5 (Rambaut and Drummond 2007) to assess convergence. It was determined
that convergence was achieved within the first 25% of sampled trees, which were then discarded
as burn-in, and the remaining trees were taken to represent the posterior probability distribution.
21
Uncorrected pairwise sequence divergences were calculated for each gene using PAUP*
(Swofford 2002).
4 Electric Waveform
4.1 EOD Recordings
Five trans-Andean species were examined for their EOD, including Gymnotus panamensis from
Panama (eight individuals), G. cylindricus and G. maculosus from Costa Rica (51 individuals),
and Gymnotus henni and Gymnotus ardilai from Colombia (17 individuals), with a total of 76
individuals recorded. A minimum of five adults were measured for each species (See Table 3 for
a summary of EOD recordings). EOD waveforms were digitized and recorded for individual fish
in the field no more than 48 hours after capture, using the head-to-tail standard and procedures
described by (Crampton et al. 2008). Fish were held in a mesh “sock" and placed in a tank of
water. Electrodes were placed directly in front of and behind the stationary fish. Water was kept
within 27°C ± 0.2°C during the day and 27°C ± 1°C at night. Conductivity was also kept
between 30-70µScm-1
, generally as close to 50µScm-1
as possible. Signals were amplified using
a custom-designed AC-coupled differential amplifier and digitized with an E-MU 0202 USB 2.0
Audio/MIDI Interface to a computer at a sampling rate of 192 kHz with 32-bit resolution. The
resultant EODs were saved in the ASCII format. The digitized signals can be visualized as a
voltage-time waveform which allows characterization of the number of phases. Phase number
was considered to be a positive or negative deviation from the 0 volt baseline greater than 1.5%
of the positive phase with highest amplitude.
4.2 EOD Character Evolution Analysis
The number of phases in adult Gymnotus range from one (monophasic) to six phases
(multiphasic). An EOD phase is characterized as a substantial deviation from the 0V baseline
(Figure 10) (Crampton and Albert 2006). While EOD phase number is generally a stereotypical
trait within species, some species with higher phase number (4+) are known to exhibit some
intraspecific variation, with phase number ranging from four to six. Due to this variability, EOD
phase number was coded as 1, 2, 3, or 4+ phases. This character was optimized as an unordered
multistate character using Maximum Likelihood and Parsimony methods in Mesquite 2.73
(Maddison and Maddison 2010). For the ML optimization the Markhov k-state 1 parameter
22
model (Mk1) of evolution was used, which considers each character change equally probable. In
order to resolve equivocal nodes in the MP optimization, ancestral states were examined in
further detail by viewing all Maximum Parsimony Reconstructions, using the MPR Mode in
Mesquite. The Maximum Likelihood consensus phylogeny was used for this analysis because it
did not include polytomies. The tree was also pruned to include only one individual per species,
except in the case of G. carapo, where it was necessary to include more than one individual to
maintain branching patterns.
23
Chapter 3 Results
1 Molecular Dataset
The cyt b dataset consisted of 1126 characters, with 545 parsimony informative characters. The
16S dataset consisted of 546 characters with 152 parsimony informative characters. The RAG2
dataset consisted of 1295 characters, with 289 parsimony informative characters. The Zic1
dataset consisted of 840 characters with 121 parsimony informative characters. The total
evidence dataset consisted of 3807 characters for 97 individuals comprising 35 Gymnotus species
and eight outgroup taxa. This dataset represents the most complete phylogenetic analysis of
Gymnotus to date. Compared to the most recent phylogenetic hypothesis (Lovejoy et al. 2010),
my dataset includes an additional nuclear gene, as well as an additional 17 species, almost
doubling the previous number of included species (Table 1). These additions include seven
species that have not yet been formally identified, as well as key trans-Andean taxa. This dataset
includes six out of the seven trans-Andean species, representing the most complete geographic
sampling of the genus.
2 Phylogenetic Relationships
2.1 Complete Dataset Analyses
Figure 15 shows the strict consensus tree of the 422 most parsimonious trees showing Gymnotus
relationships, based on two nuclear (RAG2 and Zic1) and two mitochondrial (cyt b and 16S)
genes. This phylogeny consists of 5037 steps, with a Consistency Index (CI) of 0.47, and a
Retention Index (RI) of 0.85. Figure 16 shows the results of the Maximum Likelihood analysis
using the GTR+G model (Final ML Optimization Likelihood Score=-26085.84) and Figure 17
shows the results of the Bayesian analysis, both based on two nuclear (RAG2 and Zic1) and two
mitochondrial (cyt b and 16S) genes.
Monophyly of Gymnotus and Gymnotidae is well supported across analyses. I define six major
clades, five of which were recovered by Lovejoy et al. (2010): the G1 clade (five species), G.
pantherinus, the G2 clade (four species), the G3 clade (two species), the G. cylindricus group
(three species), and the G. carapo group (20 species). These clades were consistently recovered
24
across analyses. In all analyses, there are four independent lineages that include trans-Andean
species, one of which consists of all the Middle American species. This result is consistent with
the prediction of the morphological hypothesis of Albert et al. (2004).
The three analyses differed primarily in their placement of G. pantherinus. In the MP analysis G.
pantherinus appears at the base of a clade corresponding to the G2 clade of Lovejoy et al.
(2010), consisting of G. aff. anguillaris, G. pedanopterus, G. n. sp. FRIT, and G. cataniapo. In
the ML and Bayesian analyses G. pantherinus is found to be a separate lineage representing the
sister taxa to all Gymnotus, except the G1 clade. Within the G2 clade, the positions of G.
pedanopterus and G. aff. anguillaris are not well supported in any analysis.
A new clade composed of G. tigre and G. henni was found to be the sister group to the clade
consisting of the G. cylindricus group and the G. carapo group. I define this new clade as the G3
clade. The G. cylindricus clade contains all of the Middle American species. G. panamensis was
found to form the sister group to G. cylindricus + G. maculosus. The analyses also suggested that
some G. cylindricus individuals may be more closely related to G. maculosus than to other G.
cylindricus.
Within the G. carapo group, there are five major lineages with relatively stable positions across
analyses (Figures 15, 16, 17). Clade A consists of seven species and Clade B consists of three
species. Clade C consists of G. bahianus and the „G. carapo complex‟ (three species). Clade D
consists of three species, of which two are trans-Andean in distribution. Clade E consists of the
„G. sylvius complex‟ (four species). The species composition of these clades remains the same,
except in the Parsimony analysis where G. omarorum appears as the sister taxon to clade C +
(D+E) instead of within clade B.
Some species relationships vary across analyses, including the closely related G. carapo, G.
arapaima, and G. ucumara, as well as G. sylvius and the newly discovered species G. n sp.
CORU, G. n sp. MAMA, and G. n sp. RS1. G. chaviro is sometimes nested within G. varzea and
G. mamiraua is sometimes nested within G. n. sp. ITAP. Both G. choco and G. ardilai are found
in one clade within the G. carapo group; however, some G. carapo from the Orinoco appear to
be more closely related to G. ardilai than to other G. carapo from the same region.
25
2.2 Individual Gene Analyses
Individual gene analyses were performed using MP and ML methods (Figure 18 and 19,
respectively). For these analyses, cyt b and 16S were combined into one mtDNA dataset. All
individual MP gene analyses recovered the same major clades but differed slightly in their
placement of individual taxa, particularly within the G. carapo group. The mtDNA MP analysis
could not resolve the positions of the G2 and G3 clades or G. pantherinus. The mtDNA MP
analysis also differed in its placement of G. omarorum. Both RAG2 MP and Zic1 MP analyses
exhibit a significant loss of resolution compared to the mtDNA MP dataset, particularly within
the G. carapo group. The Zic1 MP analysis did not resolve any major clades. This result is
expected based on the smaller amount of parsimony-informative characters in these datasets and
the slower rate of evolution in nuclear genes. The RAG2 MP analysis places G. pantherinus as
the sister taxon to the clade consisting of the G3 clade + (G. cylindricus group + G. carapo
group).
Individual ML gene trees also recover all major clades with slight variations in their positions
across genes. The mtDNA ML dataset places the major clades in the same positions as the total
dataset analysis. It varied from the total evidence analysis in the placement of Clade D within the
G. carapo group. The RAG2 ML analysis differed from the total evidence and mtDNA MP
datasets in the placement of G. stenoleucas and G. pantherinus. It also differed in the positions
of some clades within the G. carapo group. The Zic1 MP analysis was the most different from
the total evidence dataset with a basal G2 clade, and G. pantherinus as the sister taxon to the rest
of the species. The G1 clade was then the sister clade to the G3 clade + (G. cylindricus group +
G. carapo group). All individual genes varied somewhat in their placement of some individuals
within the G. carapo group, particularly within Clades C and D.
The topology of the individual gene phylogenies was largely consistent across analyses, with the
major clades consisting of the same species. There were some differences in arrangement of the
clades and individual species relationships, mostly within the G. carapo group. The individual
gene phylogenies generally exhibited improved resolution in the ML analyses.
26
2.3 Molecular Sequence Divergence
Uncorrected pairwise distances were compared for key species and clades. These distances were
calculated for multiple genes, but cyt b distances are presented here, because of the widespread
use of the cyt b gene in phylogenetic studies of fishes. Hereafter, divergences refer to pairwise
cyt b distances.
E. electricus was approximately 25% divergent from Gymnotus species. Interspecific
divergences within Gymnotus were generally greater than 1%. Intraspecific divergences were
generally less than 1%, with a few exceptions. The G. carapo group was found to have more
closely related species groups, while more basal clades were found to exhibit greater divergences
between species.
Trans-Andean clades were found to have varying degrees of divergence from their cis-Andean
sister clades. G. maculosus, G. cylindricus, and G. panamensis are on average 11.4% divergent
from members of their cis-Andean sister clade, the G. carapo group. G. henni is on average
11.3% divergent from its cis-Andean sister taxa G. tigre. G. choco is on average 1.5% divergent
from its cis-Andean sister taxon, G. carapo (OR). In contrast, G. carapo from the Orinoco was
only found to be between 0-0.2% diverged from G. ardilai.
Divergences between regions for the widespread G. coropinae and G. carapo were noticeably
larger than within regions. Within G. coropinae, Central Amazon individuals were 0% divergent
from each other, and individuals from the Guyanas were on average 1% divergent from each
other. Divergences between the two regions for G. coropinae were an average of 4.3%. Within
G. carapo, individuals from the Orinoco were 0.2% divergent, individuals from the Central
Amazon were 0% divergent, and individuals from the Western Amazon were 0.6% divergent.
Orinoco individuals were on average 3.9% divergent from the other regions. G. carapo from the
Central and Western Amazon constitute members of the „G. carapo complex,‟ with G. arapaima
and G. ucamara. Members of the „G. carapo complex‟ were on average 0.4% divergent. G.
bahianus was found to be approximately 1.5% diverged from the „G. carapo complex.‟
Several other closely related species groups were also found within the G. carapo group. G. n.
sp. CORU, G. n. sp. MAMA, G. n. sp. RS1 and G. sylvius were all closely related. G. n. sp.
MAMA individuals were on average 0.1% divergent; however, no individuals within this
27
complex were more than 0.36% divergent. Divergence among individuals of G. n. sp. ITAP was
approximately 1%. It was very closely related to G. mamiraua with only 1.7% divergence
between them. G. chaviro was only 0.08% divergent from G. varzea, compared to 0%
divergence among G. varzea individuals. G. n. sp. XING was found to be on average 2.7%
divergent from both G. n. sp. and G. pantanal, compared to the average of 1.3% divergence
between these two species. G. curupira and the specimens considered to be G. tigre (2019 and
2024) by Lovejoy et al. (2010) were 0.5% divergent. Finally, within the G2 clade, G. n sp. FRIT
was 11% divergent from G. cataniapo and 11.5% divergent from G. pedanopterus.
3 EOD Evolution
3.1 Individual EOD Signals
EODs of five trans-Andean species were recorded and digitized, including Gymnotus
panamensis from Panama (eight individuals), G. cylindricus and G. maculosus from Costa Rica
(51 individuals), and Gymnotus henni and Gymnotus ardilai from Colombia (17 individuals),
with a total of 76 individuals recorded. A minimum of five individuals was recorded per species
(See Table 3 for a summary of EOD recordings). Some intraspecific variation was observed
when comparing individuals of different size; however only adult EODs were included in the
analysis of EOD phase number. Phase number was considered to be a positive or negative
deviation from the 0 volt baseline greater than 1.5% of the positive phase with the highest
amplitude.
Figure 20 shows representative EOD signals of five trans-Andean species. G. cylindricus and G.
maculosus (from Costa Rica) were both confirmed to be monophasic. G. henni (from Colombia)
was also found to be monophasic. G. ardilai (from Colombia) and G. panamensis (from Panama)
were both found to be multiphasic, with tetraphasic and triphasic EODs, respectively.
3.2 Ancestral Character State Reconstruction
I used character reconstructions to trace evolutionary changes in EOD phase number across
phylogenetic reconstructions. Results were found to be consistent across tree topologies, thus I
report here the optimization of EOD phase number using Maximum Likelihood and Maximum
Parsimony methods for reconstruction ( Figure 21 and 22, respectively) using the Maximum
Likelihood consensus phylogeny. Maximum Parsimony Reconstructions of the ancestral state
28
recovered eight most parsimonious reconstructions. Ancestral states are reported as proportions
of their occurrence within the eight trees.
In both reconstruction methods, the ancestral state in the family Gymnotidae is inferred to be
monophasic and the ancestral state in the genus Gymnotus is inferred to be 4+ multiphasic. There
is a general trend of phase number reduction in most clades. The evolution of a triphasic state is
inferred in the ancestor of the clade consisting of the G3 clade, the G. cylindricus group, and the
G. carapo group. Further, a reversal to a multiphasic state is observed in at least one clade within
the G. carapo group. The optimizations suggest two independent phase number reductions in cis-
Andean clades within the G. carapo group: G. omarorum evolved a triphasic signal from a
tetraphasic ancestor, while G. obscurus evolved a biphasic signal from a triphasic ancestor. Two
independent reversals to a monophasic state are also observed, both within trans-Andean
lineages. Both G. henni and the G. cylindricus + G. maculosus clade evolved a monophasic
signal from a triphasic ancestor. For each trans-Andean clade, except G. ardilai, a reduction in
phase number compared to the cis-Andean sister group was observed.
The parsimony reconstruction method also optimizes the most parsimonious state for the
unknown EODs of G. n. sp. XING, G. bahianus, G. choco, and G. n. sp. RSI. G. bahianus, G.
choco, and G. n. sp. RSI are inferred to have tetraphasic signals and G. n. sp. XING is inferred to
have a triphasic signal.
29
Chapter 4 Discussion
1 Gymnotus Phylogeny
The work presented here represents the most complete phylogenetic analysis for Gymnotus to
date. The phylogenetic relationships proposed here support aspects of both Albert et al. (2004)
and Lovejoy et al.'s (2010) hypotheses and also clarifies some of the ambiguities in their
analyses.
In all analyses, the monophyly of Gymnotus and its position as sister group to E. electricus is
well-supported. The present analyses also find support for all five of the clades proposed by
Lovejoy et al. (2010), and suggest the addition of a new clade, called the G3 clade, composed of
G. tigre and G. henni (Figures 15, 16, 17). The G. cylindricus group was found to be the sister
clade to the G. carapo group in all analyses. All analyses also supported the G3 clade as the
sister group to these two clades. The G1 clade was always found to be the basal clade.
The position of G. pantherinus was found to be variable across analyses. It was alternately the
sister group to the G2 clade, which was then sister group to the G3 + (G. cylindricus group + G.
carapo group) clade, or the sister taxon to all clades except G1. Lovejoy et al. (2010) also
encountered this difficulty and noted that the position of G. pantherinus was not well-supported
in any analysis, including that of Albert et al. (2004). This ambiguity appears to be a
phylogenetic artefact. It is possible that the inclusion of additional molecular data or additional
species in the G1 and G2 clades will help to resolve the relationships of this species.
The trans-Andean species were found to be distributed in four independent lineages within three
separate species groups: the G. carapo group (G. choco and G. ardilai), the G. cylindricus group
(G. cylindricus, G. maculosus, and G. panamensis), and the G3 clade (G. henni). This result is
consistent with the prediction of Albert et al. (2004), although the species relationships found in
this study differ from that hypothesis.
My results confirm the monophyly of the G. cylindricus group, with the addition of G.
panamensis, which Albert et al. (2004) suggested was part of the G. pantherinus group. Albert et
al. (2004) suggested that G. panamensis was sister to G. pantanal and G. anguillaris within their
30
G. pantherinus group. This grouping was based mostly on external morphology as they had been
unable to collect internal anatomy data for G. panamensis. External morphological characters are
more susceptible to convergent evolution, which may have caused an erroneous placement of G.
panamensis. With the inclusion of G. panamensis in the G. cylindricus group, my analyses
indicate that this lineage includes all the Central American species, which appears more
parsimonious from a biogeographical perspective. My analyses support Lovejoy et al.'s (2010)
finding that the G. cylindricus group is the sister clade to the G. carapo group and not the sister
clade to the rest of the Gymnotus. The position of this clade was well-supported and stable across
analyses, which is significant for understanding patterns in Central American biogeography,
which will be discussed below.
G. henni was not included in Lovejoy et al. (2010)‟s study due to lack of available tissues, while
G. tigre was suggested to be the sister group to G. curupira. Albert et al. (2004) suggested that
G. tigre was the sister group to G. henni + G. esmeraldas. The results of the present analyses
seem to agree with the relationships proposed by Albert et al. (2004), which suggests that
although G. esmeraldas was not included in the present study, it may also belong to the G3
clade. The relationship found by Lovejoy et al. (2010) may have been the result of
misidentification, as the samples of G. tigre were obtained from juvenile fish (N. R. Lovejoy and
J. S. Albert, pers. comm.). Considering that there is only 0.5% divergence between those
individuals and G. curupira, it would suggest that they are in fact G. curupira, or else a new
closely related species, therefore they were treated as G. curupira in this study and new samples
of adult G. tigre were used.
My results confirmed the existence of the „G. carapo complex‟, consisting of G. carapo (CA), G.
carapo (WA), G. ucamara, and G. arapaima (Figure 15, 16, 17). Individuals of these three
species were consistently unresolved across analyses and often did not form monophyletic
species groups, suggesting that these species have only recently diverged. Incomplete lineage
sorting in this group is supported by the low divergence (~0.4%). Albert et al. (2004) originally
included G. carapo, G. ucamara, G. arapaima, and G. choco in the „G. carapo complex.‟
Lovejoy et al. (2010) confirmed the existence of this complex, but were not able to include G.
choco in their analysis due to a lack of tissue samples. In my analysis, G. choco was not included
in what I refer to as the „G. carapo complex,‟ but instead, groups with G. carapo (OR) + G.
ardilai. G. carapo (OR) was found to be on average 3.9% divergent from G. carapo of other
31
regions. This evidence suggests that the specimens of G. carapo from the Orinoco may represent
a distinct species. In the past, many specimens of Gymnotus were automatically considered to be
G. carapo based on the limited taxonomic work that had been done on Gymnotus (Albert et al.
1999). This practice resulted in specimens of diverse phenotypes being labelled G. carapo in
museum collections, which gave rise to the idea that this species has an extremely broad
geographic distribution. It is likely that many of these specimens represent distinct species.
These results further support the suggestion of Albert et al. (1999, 2004) that G. carapo is a
paraphyletic species and that its taxonomy and population genetics warrant further investigation.
In a similar vein, the specimens of G. coropinae from the Central Amazon and the Guyanas
exhibit an average divergence of 4.3%. These populations may be in the process of becoming
reproductively isolated and investigations into the morphology and population genetics of this
species could be interesting.
This study included several taxa that have been suggested to represent new species. Within the
G2 clade, G. n sp. FRIT was 11% divergent from G. cataniapo and 11.5% divergent from G.
pedanopterus, suggesting that it is in fact a distinct species. G. n. sp. XING was also found to be
relatively divergent (2.7%) from both G. n. sp. and G. pantanal, compared to the 1.3%
divergence between these two species. Additional evidence will be required to corroborate the
status of G. n. sp. as a distinct species. Divergence among individuals of G. n. sp. ITAP was
approximately 1%. It was very closely related to G. mamiraua with only 1.7% divergence
between them. These two species were not always found to be reciprocally monophyletic,
suggesting that G. n. sp. ITAP may represent a variation of G. mamiraua. Finally, G. n. sp.
CORU, G. n. sp. MAMA, G. n. sp. RS1, and G. sylvius were all observed to be very closely
related, forming a species complex that I refer to as the „G. sylvius complex‟ The analyses show
that these species do not always form species groups. G. n. sp. MAMA individuals exhibited on
average 0.1% intraspecific divergence; however, no individuals within this complex were more
than 0.36% divergent from each other. Additional evidence will be required to confirm the status
and relationships of this group.
2 Biogeography of the trans-Andean species
The trans-Andean species were found to be distributed in four independent lineages within three
separate species groups: the G. carapo group (G. choco and G. ardilai), the G. cylindricus group
32
(G. cylindricus, G. maculosus, and G. panamensis), and the G3 clade (G. henni). This result is
consistent with the prediction of Albert et al. (2004). Albert et al. (2004) suggested some
biogeographic scenarios for Gymnotus based on the relationships in their phylogeny. The
multiple trans-Andean lineages are inferred to have diverged as a result of vicariance due to the
rise of the Andes approximately 12 mya. Assuming that the trans-Andean lineages diverged
approximately 12 mya, much of the diversity in Gymnotus can be inferred to predate this time
period as there was already considerable lineage diversity within the genus.
If all trans-Andean lineages diverged as a result of Andean uplift, they should exhibit similar
amounts of diversification from their closest cis-Andean sister group (assuming relatively equal
rates of molecular evolution). In fact, when comparing uncorrected pairwise divergences, the
trans-Andean clades were found to have varying degrees of divergence from their cis-Andean
sister clades. G. maculosus, G. cylindricus, and G. panamensis are on average 11.4% divergent
from members of their cis-Andean sister clade, the G. carapo group. G. henni is on average
11.3% divergent from its cis-Andean sister species, G. tigre. In contrast, G. choco is on average
1.5% divergent from its cis-Andean sister taxon, G. carapo (OR) and G. ardilai was only found
to be between 0-0.2% diverged from cis-Andean G. carapo (OR). Thus, amounts of cis/trans
divergence are relatively similar for the G. cylindricus group and G. henni lineages, while much
less cis/trans divergence is evident for the G. choco and G. ardilai lineages. If G. henni and the
G. cylindricus group are inferred to have diverged as a result of the uplift of the Andes, then G.
choco and G. ardilai may have diverged more recently, via alternative biogeographic pathways.
This pattern could possibly be explained by stream capture events or human-facilitated dispersal.
The small amount of divergence between G. ardilai and G. carapo (OR), as well as the restricted
distribution of the former (Maldonado-Ocampo and Albert 2004), could indicate that G. ardilai
represents a human introduction of G. carapo (OR) into the trans-Andean region.
My results clarify the biogeography of the Central American Gymnotus species. While Albert et
al. (2004) proposed that two lineages of Gymnotus (a G. panamensis lineage and a G. cylindricus
+ G. maculosus lineage) were present in Central America; my analyses show that these lineages
represent a single monophyletic clade. The timing of the dispersal event of this lineage into
Central America is somewhat contentious. Myers (1966) proposed that due to the relatively
species-poor fauna of primary freshwater fish species in Central America, it was likely that those
groups, including Gymnotus, were relatively recent invaders, most probably making use of the
33
Panamanian landbridge approximately 3mya. Conversely, Bussing (1976, 1985) suggested that
some fishes, including Gymnotus, reached Central America much earlier, by the late Cretaceous
or Paleocene, approximately 65mya. At this time, an ancient landbridge between North and
South America is hypothesized to have existed, which would have allowed dispersal into Central
America (Briggs 1994). This hypothesis is partly based on the fact that Gymnotus is the only
gymnotiform that is distributed farther North than Costa Rica. Considering the long time spans
involved in freshwater dispersal across land-masses, it follows that Gymnotus could only have
achieved such a Northerly distribution over extremely long time periods.
The phylogeny of Albert et al. (2004) provided some support for the hypothesis that the G.
cylindricus group represents a relatively ancient invasion into Central America. The trans-
Andean lineages were distributed in multiple lineages, with the G. cylindricus group representing
the sister clade to all other Gymnotus species (Figure 5). If the nested trans-Andean lineages are
considered to have evolved as a result of Andean uplift approximately 12 mya, then the G.
cylindricus group can be inferred to have evolved much earlier, thus providing a much more
ancient timeframe for dispersal into Central America. More recently, Lovejoy et al. (2010)
proposed that the G. cylindricus group was not the sister lineage to all other Gymnotus species,
but occupies a relatively nested position within Gymnotus (Figure 6). My results agree with this
assessment, although updated divergence time estimates will further clarify the issue.
3 Electric Signal Evolution
3.1 A Complicated History
Five trans-Andean species were examined for their EOD. G. cylindricus and G. maculosus (from
Costa Rica) were both confirmed to be monophasic. G. henni (from Colombia) was also found to
be monophasic. G. ardilai (from Colombia) was found to be tetraphasic and G. panamensis
(from Panama) was found to be triphasic. All trans-Andean taxa, except for G. ardilai, seem to
show an evolutionary reduction in phase number; however, only three of the five examined
trans-Andean species exhibits a monophasic signal as was predicted by the Predator Avoidance
Hypothesis (Stoddard 1999, 2002a, 2002b). Both G. henni and the G. cylindricus + G. maculosus
clade evolved a monophasic signal from a triphasic ancestor.
34
The G. cylindricus group was found to be relatively well-nested in my phylogeny and was not
recovered as the sister group to all other species as suggested by Albert et al. (2004). This
position agrees with the phylogeny of Lovejoy et al. (2010), although it does change the
ancestral EOD state reconstruction in Gymnotus. In my analyses, the plesiomorphic condition in
Gymnotus is the 4+ multiphasic state, while the ancestral condition in Gymnotidae is inferred to
be monophasic (Figure 21 and 22). This suggests that the ancestor of Gymnotus evolved a
multiphasic signal which was subsequently reduced in phase number in other clades. A reduction
in phase number is inferred in the ancestor of the clade consisting of the G3 clade, the G.
cylindricus group, and the G. carapo group, which necessitates a reversal to the ancestral
multiphasic state in at least one clade within the G. carapo group. The optimization also suggests
two independent phase number reductions in cis-Andean clades within the G. carapo group. G.
omarorum is observed to have evolved a triphasic signal from a tetraphasic ancestor, while G.
obscurus evolved a biphasic signal from a triphasic ancestor. This analysis suggests a
complicated history of evolutionary reversals and reductions within this group. Below, I consider
why both cis- and trans-Andean species may evolve reduced phase number from a multiphasic
ancestor and why multiphasic signals are present in trans-Andean species.
These results were not consistent with the prediction of the Predator Avoidance Hypothesis that
all trans-Andean species should have monophasic signals; however, it may be that the
complexity of this system prevents simple patterns of character evolution from being observed.
The many selective pressures influencing electric signal evolution could preclude one selective
pressure from taking precedence above the others. The biology of this group is complex, so
perhaps the fact that the only examples of evolutionary reversal to monophasy are observed in
trans-Andean lineages does support the Predator Avoidance Hypothesis. It is possible that some
lineages are consistent with the Predator Avoidance Hypothesis, while some are subject to
stronger selective pressure from other forces. I have postulated several hypotheses to explain
these patterns.
First, my results may indicate that there are more significant levels of predation in the trans-
Andean region than previously thought. Predation pressure has not been explicitly studied in the
trans-Andean region, so the multiphasic signals of some trans-Andean species could represent
adaptations to avoid electroreceptive predators that are outside the key electroreceptive predator
groups that have been identified in South America. Electric eels are not known from this region,
35
and the diversity of large pimelodid catfish is reduced; however, there could be other
electroreceptive predators present in sufficient abundance to influence EOD evolution. Stoddard
(1999, 2002a, 2002b) has made a compelling case for the strength of predation pressure as an
evolutionary force shaping EOD evolution, so even weak predation pressure may represent a
selective force. As such, until predation pressure in the trans-Andean region is explicitly
quantified, I cannot rule this hypothesis out.
Conversely, if a reduction in phase number is considered to represent an increase in the amount
of low-frequency energy of the electric signal, my results could be reconciled with the Predator
Avoidance Hypothesis. Each trans-Andean clade except G. ardilai exhibits a reduction in EOD
phase number relative to its cis-Andean sister clade, which could represent a reduction of the
anti-predator adaptation of multiphasy in a region where predation pressure is reduced. The loss
of anti-predator behaviour takes time to occur, especially when some predators are removed but
others remain (Blumstein 2002, 2006, Blumstein and Daniel 2005). It is possible that while some
trans-Andean species retain the multiphasic state due to evolutionary persistence, the reduction
in phase number represents the first step towards a reversal to monophasy. This hypothesis
assumes that there is an adaptive benefit to having a low-frequency energy EOD, which is
considered below (Section 3.4).
3.2 G. ardilai may be a recent introduction
G. ardilai is the only trans-Andean species which does not exhibit a reduction in phase number
from its closest cis-Andean sister group. Above, I suggest that perhaps there is additional
predation pressure in certain trans-Andean regions that selects for a multiphasic signal.
Alternately, biogeographic evidence may provide some explanations. There is 0-0.2%
divergence between G. ardilai and G. carapo from the Orinoco. One of the diversification
scenarios suggests that G. ardilai may represent a relatively recent introduction of G. carapo into
the region. If this was the case, G. ardilai would not have been subject to the same selection
pressures as other trans-Andean species throughout its evolutionary history. If it diverged from
G. carapo only very recently, it is not surprising that it still retains the tetraphasic signal.
36
3.3 Mechanisms for a return to monophasy
In order for a reversal to a monophasic state to be possible, there must be physiological
mechanisms that allow for the production of a monophasic EOD from a multiphasic ancestral
state. The most likely mechanism in Gymnotus is a paedomorphic retention of the monophasic
larval EOD. The electric organ of all pulse-type gymnotiforms is derived from hypaxial muscle.
This electric organ remains the same throughout development in Gymnotus (Albert and
Crampton 2005b, Pereira et al. 2007). Monophasic discharges are produced by an action
potential that causes the innervated caudal face of the electrocyte to depolarize, inducing ion
flow through a sodium-potassium pump (Figure 10). This flow of ions causes depolarization of
the next electrocyte and so on, creating a current through the electric organ. In multiphasic
species, subsequent to the depolarization of the caudal face, the rostral face of the electrocyte
will depolarize and create a current in the opposite direction, which creates the next phase that is
opposite in polarity to the initial phase (Hopkins 1988, Stoddard 2002a). Further complexity is
generated by the use of accessory electric organs or special columns of electrocytes that are
unique in their development, sometimes with innervation on both faces (Hopkins 1988). In the
ontogeny of some tetraphasic species, it has been found that the larvae progress from one to four
phases sequentially as they grow. This pattern indicates that EOD phase number phenotype is an
indication of the complexity of the EOD that is achieved during ontogeny (Crampton and
Hopkins 2005, Pereira et al. 2007). Thus, the mechanism for a multiphasic species to evolve to a
monophasic species could simply be the retention of the larval monophasic signal and the loss of
accessory electric organs or the cues that cause additional depolarizations.
3.4 Adaptive significance of low-frequency energy
My results indicate a trend towards reduction in EOD phase number within Gymnotus. If a
reduction in phase number is considered to increase the amount of low-frequency energy in the
EOD, this pattern may suggest that there is an adaptive benefit to having a low-frequency energy
EOD that is most likely related to the two main functions of electrolocation and
electrocommunication.
First, if low-frequency energy has an adaptive benefit for navigation, monophasic species might
be expected to exhibit greater spatial acuity or alternately, command a greater signal space.
There have been no experiments done to date on the differences in spatial acuity of monophasic
37
vs. multiphasic species. Conversely, there has been much research generated on the active signal
space of electric fish. It has been found that EOD amplitude is related to the distance that the
signal is projected from the body (Hopkins 1999, Stoddard and Salazar 2011). All strongly
electric fish exhibit a monophasic discharge, prompting the suggestion that monophasic signals
maximize electrical current output (Stoddard 2002b). A Brachyhypopomus species from the
Amazon has a monophasic signal, which has much greater amplitude than its multiphasic
congeners. In fact, it has such a strong discharge that it has been known to confuse ichthyologists
who mistake the signal for that of an electric eel (Stoddard 1999, 2002a, 2002b). It has been
proposed to be a Batesian mimic of the electric eel; however, no studies have yet been done to
test whether it actually deceives electroreceptive predators.
Higher amplitudes, which are associated with monophasic signals, increase the active signal
space for an individual fish (Hopkins 1999, Stoddard and Salazar 2011). This could be important
both in navigation (increasing the distance at which they can forage, etc.) and communication
(increasing the distance at which they can detect potential mates, etc.). The ability to sense
electric signals within a greater signal space also allows a fish to command a greater territory.
Several Gymnotus species are known to be territorial (Albert and Crampton 2003, 2005a). A
larger territory could potentially help them to command a larger number of high quality
oviposition sites. Access to high quality oviposition sites could influence a female‟s choice in the
wild, suggesting that males which are more successful at acquiring and maintaining a high
quality territory would be more desirable by females (Curtis and Stoddard 2003). Having a
greater signal range could also allow these males the ability to sense when other males try to
trespass or when females enter their territory across greater distances. Male Brachyhypopomus
were found to increase their EOD amplitude much more rapidly when presented with males than
with females (Franchina et al. 2001), suggesting that EOD amplitude is important in dominance
signalling. Stronger signals can also increase stimulation of the electroreceptors essentially
providing a more potent signal to any potential receiver (Stoddard and Salazar 2011).
Greater EOD amplitude and duration may act to improve detection and thus increase the
probability of mating (Stoddard 2002a). Greater amplitude would increase the probability of
detection by increasing signal space, while an increase in duration and pulse rate increases the
chances that male EODs will overlap those of females. Temporal overlap in EOD signals
actually increases the sensitivity of a fish‟s electroreceptors to other EOD signals because the
38
electroreceptors are tuned specifically to detect distortion in the signal (Stoddard 2002a). These
spatially and temporally separated cues allow the fish to distinguish between self-generated and
conspecific-generated EOD signals, effectively separating the functions of electrolocation and
electrocommunication (Aguilera et al. 2001).
Monophasic signals could therefore be more useful for electrolocation and electrocommunication
across longer distances. Trans-Andean species tend to inhabit areas where they are the only
Gymnotus species in the region. Studies of population ecology are lacking; however, it may be
that these species occur in low population densities. In these situations it would be adaptive to
maximize the likelihood of detection by a conspecific by increasing the active signal space. In
territorial species, greater signal range also increases the size of the territory which may provide
access to higher quality foraging sites and oviposition sites to attract females.
Ancestral electric fish are suspected to have had monophasic signals that would have included
more low-frequency energy (Stoddard 2002a, 2002b). Due to the importance of electric courtship
in extant species, there is no reason to suspect that ancient females were not courted in the same
way. Ancient courtship signals would likely have included a large amount of low-frequency
energy. Modern females may have retained their original preference for low-frequency energy in
courtship signals; however, this has not been empirically proven in laboratory studies (Stoddard
2002a). It has been found that increased duration of the second phase in some Brachyhypopomus
species at peak mating times, actually increases the amount of low-frequency energy in the
signal, thus providing some anecdotal support that females may be attracted to low-frequency
energy (Stoddard 2006).
Studies of mating preferences have found that females tend to prefer males of larger body size
and longer body length (Stoddard 2002a, Curtis and Stoddard 2003). In the lab it has been shown
that body size is correlated with the amount of food provided, suggesting that body size in the
wild could be an indicator of foraging ability. EOD amplitude has been positively correlated with
both body size and body length (Franchina et al. 2001, Curtis and Stoddard 2003, Stoddard
2006). Since females are not likely to assess a male‟s body size visually, EOD amplitude could
be a cue that allows females to determine body size and therefore make assessments about a
male‟s quality. These results suggest that females may in fact exhibit a preference for EOD
signals with greater amplitude and duration (Stoddard 2002a, Curtis and Stoddard 2003). At this
39
stage, there is insufficient evidence to discern whether these EOD traits are attractive to females
or if they simply increase the probability of detection. Further lab tests are needed to clarify these
issues of female preference.
The introduction of additional low-frequency energy into the EOD of multiphasic species also
supports the idea that certain EOD signals are indicative of male quality. Males that input more
low-frequency energy in their signals are more susceptible to predation. Low-frequency energy
in courtship signals may have evolved as sexual handicaps, advertising male vigour despite their
conspicuousness to predators (Zahavi 1975). These low-frequency signals could thus be an
honest indicator of a male‟s survival ability. The more low-frequency energy in the courtship
signal, the more conspicuous that male is to predators. If a male can evade predators despite a
large amount of low-frequency energy in his signal, it could indicate that he has superior survival
ability. Male Brachyhypopomus actually emit a specialized signal called a “chirp” during
courtship, which resembles a rapid series of EODs with a significantly reduced or completely
lacking second phase. These signals exhibit significant low-frequency energy which would fall
in the range of the ampullary electroreceptors (Stoddard 2002a). Low-frequency energy has also
been found to be important in courtship in Eigenmannia and Apteronotus (Hopkins 1974,
Hagedorn and Heiligenberg 1985, Stoddard 2006). This low-frequency energy can have serious
consequences, as it has been found that approximately half of the sexually mature males of
Brachyhypopomus pinnicaudatus showed some signs of predation in the form of regenerating
tails, whereas almost all of the females‟ tails were intact. It has also been found that mature
males of Brachyhypopomus diazi actually disappear entirely from streams during breeding
season, while mature females exhibit no such mortality (Stoddard 2002a). It could also be
possible that low-frequency energy is not attractive to females per se, but acts as a cue to induce
spawning (Hagedorn and Heiligenberg 1985, Stoddard 2006). Hagedorn and Heiligenberg (1985)
found that spawning in female Eigenmannia virescens could be stimulated by the electrical
playback of low-frequency energy „chirps‟. In this case, monophasic species would not need to
modify their signal to elicit a courtship response, as their signal would always carry this low-
frequency energy. In a predation-free environment, species may revert to a simpler signal to
accomplish this purpose, rather than retain a more complex signal that requires costly
modifications.
40
Courtship has also been found to represent a significant energy expenditure for gymnotiforms.
Hopkins (1999) estimated the amount of energy expended by electrogenesis, based on current
and voltage of a mormyrid, to represent only about 1% of the daily basal metabolic rate. This
estimate would suggest that the energetic cost of the EOD is quite small; however, this estimate
only considered the standard EOD used for electrolocation. Males of some Brachyhypopomus
species will increase sexually dimorphic characters, such as amplitude, duration, and pulse rate at
peak courtship times and reduce them during non-mating hours in a form of courtship
communication (Hopkins 1999, Silva et al. 1999, Stoddard 2002a, Albert and Crampton 2005a,
Salazar and Stoddard 2008). This modification increases the amount of low-frequency energy in
the signal (Salazar and Stoddard 2008). Increasing amplitude and duration of the EOD increases
the total amount of energy that a fish would need to expend on the EOD (Hopkins 1999,
Stoddard 2002a). In addition, the EOD has been found to be more costly for males than females
of B. pinnicaudatus and to require more energy at night than during the day. The total energetic
expense of the EOD was 3.4% of the energy budget in females, but 11-22.5% of the energy
budget in males (Salazar and Stoddard 2008). This result suggests that the modification or
modulation of the EOD can represent a significant energetic cost to males, which is too costly to
maintain when the benefits are low. Reduction of EOD amplitude and duration during the day
reduced the energetic cost by 38-72% in males, but only 26% in females. Along with the
observation that males will reduce EOD amplitude and duration during social isolation, this
pattern suggests that males will reduce these costly modifications in order to save energy when
they are not likely to accrue any social benefit (Franchina et al. 2001, Salazar and Stoddard 2008,
2009). The base rate for electrogenesis seems to be very small, whereas modification for greater
amplitude or duration can be costly. Monophasic species have no need to modify their signal to
introduce low-frequency energy, so they may be able to allocate their energy budget to growth,
which would provide them with an advantage in territoriality and mating.
Reversal to a monophasic signal may therefore reduce the amount the amount of energy that a
fish is required to spend on costly modulations to introduce low-frequency energy into the signal.
It may also allow a fish to have increased signal amplitude, therefore allowing it to defend a
larger territory and obtain more matings. These selective pressures may become dominant in
areas where predation pressure and species recognition pressures are reduced. It has been
suggested that the increase in phase number allows for more variation in the EOD, increasing the
41
possibilities for species-specific signals; however, most trans-Andean species do not occur in
sympatry with any other Gymnotus species, and therefore are not under selective pressure for
EOD divergence. In these cases where a multiphasic signal is not required, a simple monophasic
signal may be more beneficial to other aspects of the biology of these fish.
3.5 Cis-Andean Reductions in Phase Number
The previous section delineated some hypotheses for why a monophasic signal may be beneficial
in a region where predation pressure is reduced; however, that does not offer an explanation for
why a reduction in phase number is adaptive in regions where predation pressure is high. In two
clades of cis-Andean species there have been independent reductions in phase number. These
individuals would be more susceptible to predation. The social benefits of the low-frequency
energy may outweigh the risk of predation in some species or populations, especially where the
ratio of males to females is high, or there are many different species of electric fish occurring in
sympatry.
These fish may have also evolved other adaptive behaviours that allow them to benefit from this
low-frequency energy while still evading predation. Circadian rhythms in courtship signals allow
males to maximize the benefits of the risky signal by increasing low-frequency energy at peak
mating times when they are most likely to benefit from it, and reducing this low-frequency
energy when the benefits would be low and the risks would be high (Stoddard et al. 2006, 2007,
Salazar and Stoddard 2008). Multiphasic species may also have evolved novel anti-predator
behaviours to assist in evading electroreceptive predation. Stoddard (2006) observed that when
Brachyhypopomus was injected with any solution, they exhibited a 40-60% drop in their EOD
amplitude, which returned to normal after two to five minutes. He suggested that the drop in
amplitude would make it more difficult for an electroreceptive predator to locate the fish as it
escaped and could therefore be considered a behavioural response to what the fish perceived as a
predation attempt. Behavioural responses to avoiding predation may be of critical importance in
these cis-Andean species.
3.6 Abiotic Selective Pressures
The adaptive benefits above all considered biotic selective pressures. There could also be an
influence of abiotic factors on signal evolution. Electric signals are subject to a wide array of
42
abiotic selective pressures, related both to efficient electrolocation and reliable transmission of
communication signals (Crampton and Albert 2006). The electric signal can be affected by
dissolved oxygen, conductivity, temperature, flow, and habitat (Crampton and Albert 2006).
Gymnotiforms, for example, are restricted to freshwater and cannot tolerate any degree of
brackish water because the increased conductivity prevents the proper functioning of the
electrosensory system (Albert 2000, Albert and Crampton 2005b). Adaptation to a particular
habitat has been suggested to constrain electric signal evolution, such as the adaptation of wave-
type species to fast flowing, well-oxygenated environments (Hopkins and Heiligenberg 1978,
Crampton 1998, Crampton and Albert 2006). Albert et al. (2004) found that all trans-Andean
species were restricted to non-floodplain terra firme streams that exhibited low conductivity.
This habitat type could provide an advantage for individuals exhibiting low-frequency energy
EODs. Alternately, the increase in low-frequency energy could constrain species with this signal
type to that particular habitat. Conversely, it has been suggested that physical factors may not
affect the evolution of phase number in Gymnotus at all (Crampton et al. 2011). More studies are
needed to examine the basic biology of these fish before the abiotic factors influencing trans-
Andean EOD evolution can be explained.
3.7 Corollaries
It is important to remember that most of the studies described above in Sections 3.4 and 3.5 have
been conducted using various species of Brachyhypopomus. While the genus also exhibits a
pulse-type signal, it does exhibit certain differences from Gymnotus. For example, Gymnotus
species are not known to modulate their signal during courtship (Crampton and Albert 2006).
Therefore, the evidence presented here would be greatly supplemented by additional studies with
Gymnotus. Recently, G. coatesi and G. curupira have been found to possess sexually dimorphic
signals. Males of these species and those of G. varzea, EODs were observed to contain an
increase of low-frequency energy compared to immature adults and females. Males of G.
arapaima also exhibited more low-frequency energy in their signals than females (Crampton et
al. 2011). More studies are needed to determine if these species exhibit electric courtship signals
as well.
The importance of territoriality in Gymnotus could also affect EOD evolution. Territoriality
could select for more stable EODs. It would be adaptive for a territorial species to be able to
43
recognize individuals, which would require individually distinct EOD components to be
consistent over a period of time. This would likely select against the extreme signal plasticity
that is seen in Brachyhypopomus (Stoddard 2006). Additionally, the tendency for males to have
an increased role in parental care in Gymnotus, could suggest the possibility for male choice as
well as female choice in Gymnotus (Crampton et al. 2011). A two-way mate choice system
would impose an additional set of constraints on the evolution of EOD signals.
Studies examining the differences in energy expenditure and navigational capabilities between
monophasic and multiphasic species are needed. Territoriality could be highly important in
influencing the evolution of EOD parameters, yet there are almost no studies looking at
territorial behaviour in electric fish. There have been some studies completed on dominance
signalling (Hopkins 1974, Hagedorn and Heiligenberg 1985, Stoddard 2002a, Salazar and
Stoddard 2008); however, they have mostly concerned wave-type fish. Studies of the distribution
of electroreceptive predators are also needed. To date, no studies have examined electroreceptive
predation behaviour in the wild, which would greatly inform studies of predator avoidance
adaptations.
It is also critical to remember that many experiments use EOD playbacks to elicit responses from
other electroreceptive fish. Unfortunately, EOD playbacks lack the temporal interactions and
spatial heterogeneity of natural EODs (Curtis and Stoddard 2003). Their simplicity may not
induce the full range of responses from receivers that may be observed in the wild. Experiments
using live fish would be more conclusive. More accurate models of the spatial and temporal
aspects of the EOD could also be used to create more realistic EOD recordings that would
improve the reliability of playback experiments.
4 Future Directions
Future phylogenetic studies on Gymnotus should include more species from the G1 and G2
clades in order to help clarify the position of G. pantherinus. Studies including faster-evolving
genes should also help to clarify relationships between the species complexes within the G.
carapo group. Future work should also endeavour to estimate the timing of divergence of the
trans-Andean lineages. Updated estimates of divergence times will not only assess my
hypothesis that the trans-Andean lineages diverged at different times, but will help to clarify the
time periods and therefore the potential cause for this divergence. These estimates may even help
44
to clarify the timing of dispersal of the G. cylindricus group into Central America. Ideally, future
work will also be able to include both tissues and EOD recordings from the two remaining
unknown trans-Andean species, G. esmeraldas and G. choco.
Further research on the evolution of the electric signal would be greatly enhanced by studies
using live specimens of a more diverse array of species, including Gymnotus and other
gymnotiform species. A greater number of species will help to clarify if most species are
evolving in the same way, or if they have different strategies for coping with the same selection
pressures.
In order to truly evaluate the Predator Avoidance Hypothesis, additional studies on the level of
electroreceptive predation pressure in both cis- and trans-Andean habitats are needed. Studying
electroreceptive predation behaviour in the wild will help to clarify its importance in
gymnotiform communities and will likely uncover interesting anti-predator behaviour in various
gymnotiform species.
Additional work is needed to test the hypothesis that there is an adaptive benefit to low-
frequency energy. Research on the amplitudes, foraging ability, and sensory acuity of
monophasic vs. multiphasic species would be beneficial. This information would be especially
useful when combined with studies of territorial behaviour in gymnotiforms. In addition, a large
amount of work needs to be done to test female preference and the importance of low-frequency
energy in courtship and spawning.
Studies on the energetic costs of different types of electric signals, particularly the difference
between monophasic vs. multiphasic and wave-type vs. pulse-type signals would suggest
whether or not energetic costs play a role in the evolution of electric signals. Finally, clarifying
the effect of abiotic parameters on the electric signal will not only help to clarify how these
factors affect electric signal evolution, but how abiotic factors influence the distribution of
electric fish.
5 Conclusions
This work represents the most complete phylogenetic analysis of Gymnotus to date, almost
doubling the number of species included in the previous molecular phylogeny. My analyses
45
included seven species that have not yet been formally identified, as well as six out of the seven
known trans-Andean species. The resultant phylogenetic hypotheses provide us with a better
understanding of the relationships between the major lineages in Gymnotus. The trans-Andean
species were found to be distributed in four distinct lineages, with the G. cylindricus group
forming a monophyletic clade, composed of all the Central American species. The relative
differences in the amount of divergence between the trans-Andean lineages and their cis-Andean
sister groups suggest that they did not all arise due to the uplift of the Andes as was previously
believed. The monophyletic grouping of all Central American species suggests a single dispersal
event into Central America. Based on these patterns, further divergence time estimates will help
to clarify biogeographic patterns of diversification. Further study is needed to understand the
timing of these events and to trace the patterns of dispersal and vicariance.
My work also provides new information on EOD waveforms for five trans-Andean species, as
well as an analysis of the evolution of phase number. My results suggest that the ancestral state
in Gymnotidae is a monophasic discharge, while the ancestral state in Gymnotus is a 4+
multiphasic state. Not all of the trans-Andean species were found to be monophasic as was
suggested by the Predator Avoidance Hypothesis; however, a general trend of reduction in phase
number was observed. This reduction in phase number could represent an adaptive increase in
low-frequency energy of the EOD signal. Low-frequency energy could be advantageous for
reasons of increased signal space, sexual selection, and energetic costs. Testing these hypotheses
should lay the groundwork for further studies on Gymnotus, such as the variation and evolution
of other aspects of EOD parameters, providing novel implications for species recognition and
mate choice.
46
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Table 1. List of specimens included in study.
Speciesa Specimen Voucher Locality
Brachyhypopomus brevirostris 2617 UF 116556 Rio Nanay, Peru
Brachyhypopomus diazi 305 UF 174334 Rio Las Marias, Venezuela
Brachyhypopomus diazi 2408 UF 174334 Rio Albergatón, Venezuela
Brachyhypopomus n. sp. PAL 2432 UF 148572 Rio Palenque, Ecuador
Electrophorus electricus 2026 MZUSP 103218 Lago Secretaria, Brazil
Electrophorus electricus 2619 UF 116585 Rio Nanay, Peru
Gymnotus aff. anguillaris 2091 AUM 36616 Rio Aponwao, Guyana
Gymnotus arapaima 2002 MZUSP 75179 Lago Mamirauá, Brazil
Gymnotus arapaima 2003 MZUSP 103219 Lago Mamirauá, Brazil
Gymnotus ardilai 8175 IAvHP 11511 Rio de Oro, Colombia
Gymnotus ardilai 8186 IAvHP 11510 Rio de Oro, Colombia
Gymnotus bahianus 7244 No Voucher Rio Almada, Brazil
Gymnotus bahianus 7245 No Voucher Rio Almada, Brazil
Gymnotus carapo (CA) 2004 MZUSP 76066 Lago Secretaria, Brazil
Gymnotus carapo (CA) 2030 MZUSP 76066 Lago Secretaria, Brazil
Gymnotus carapo (WA) 2006 UF 131129 Rio Amazonas, Peru
Gymnotus carapo (WA) 2007 UF 131129 Rio Amazonas, Peru
Gymnotus carapo (OR) 2040 UF 174335 Rio Guaratico, Venezuela
Gymnotus carapo (OR) 2041 UF 174335 Rio Guaratico, Venezuela
Gymnotus cataniapo 2062 UF 174330 Rio Atabapo, Venezuela
Gymnotus cataniapo 2063 UF 174332 Rio Cataniapo, Venezuela
Gymnotus chaviro 7357 33715 No Locality
Gymnotus chaviro 7358 33729 No Locality
Gymnotus choco 8209 IAvHP 10646 Rio Atrato, Colombia
Gymnotus coatesi 2042 MCP 34471 Lago Tefé, Brazil
Gymnotus coatesi 2043 MCP 34472 Rio Tefé, Brazil
Gymnotus coropinae (CA) 2010 MZUSP 75188 Lago Tefé, Brazil
Gymnotus coropinae (CA) 2025 MZUSP 60611 Lago Tefé, Brazil
Gymnotus coropinae (GU) 2035 ANSP 179126 Sauriwau River, Guyana
Gymnotus coropinae (GU) 2036 AUM 35848 Sauriwau River, Guyana
Gymnotus coropinae (GU) 2037 ANSP 179127 Mazaruni River, Guyana
Gymnotus coropinae (GU) 2038 ANSP 179127 Mazaruni River, Guyana
Gymnotus curupira 2009 MZUSP 75148 Lago Tefé, Brazil
Gymnotus curupira 2019 UF 122823 Rio Amazonas, Peru
Gymnotus curupira 2021 MZUSP 75146 Lago Tefé, Brazil
Gymnotus curupira 2024 UF 122821 Rio Amazonas, Peru
Gymnotus cylindricus 2092 ROM 84772 Rio Tortuguero, Costa Rica
Gymnotus cylindricus 2093 ROM 84772 Rio Tortuguero, Costa Rica
Gymnotus cylindricus 2094 ROM 84772 Rio Tortuguero, Costa Rica
Gymnotus henni 7276 IAvH-BT 11598 Rio Dagua, Colombia
Gymnotus henni 7277 IAvH-BT 11599 Rio Dagua, Colombia
Gymnotus henni 8189 IMCN 4521 Rio Dagua, Colombia
Gymnotus henni 8193 IMCN 4521 Rio Dagua, Colombia
Gymnotus henni 8207 IAvHP 11359 Colombia
Gymnotus henni 8230 STRI-01589 Rio San Juan, Colombia
Gymnotus henni 8231 STRI-01589 Rio San Juan, Colombia
Gymnotus javari 2020 UF 122824 Rio Amazonas, Peru
Gymnotus jonasi 2016 MZUSP 103220 Rio Solimões, Brazil
Gymnotus jonasi 2471 UF 131410 Rio Ucayali, Peru
Gymnotus maculosus 8126 ROM 89775 Rio Higueron, Costa Rica
55
Gymnotus maculosus 8137 ROM 89778 Rio Montenegro, Costa Rica
Gymnotus maculosus 8169 ROM 89784 Nicoya, Costa Rica
Gymnotus maculosus 8213 STRI-01587 Rio Nosara, Costa Rica
Gymnotus mamiraua 2012 MZUSP 103221 Rio Solimões, Brazil
Gymnotus mamiraua 2013 MCP 29805 Rio Solimões, Brazil
Gymnotus n. sp. 7104 No Voucher Rio Beni, Bolivia
Gymnotus n. sp. 7105 No Voucher Rio Beni, Bolivia
Gymnotus n. sp. CORU 2558 No Voucher Brazil
Gymnotus n. sp. FRIT 7109 No Voucher Tefe, Amazonas, Brazil
Gymnotus n. sp. ITAP 2559 No Voucher Brazil
Gymnotus n. sp. ITAP 7071 No Voucher Parana, Argentina
Gymnotus n. sp. ITAP 7072 No Voucher Parana, Argentina
Gymnotus n. sp. ITAP 7074 No Voucher Parana, Argentina
Gymnotus n. sp. ITAP 7075 No Voucher Parana, Argentina
Gymnotus n. sp. MAMA 7065 No Voucher Parana, Argentina
Gymnotus n. sp. MAMA 7066 No Voucher Parana, Argentina
Gymnotus n. sp. MAMA 7067 No Voucher Parana, Argentina
Gymnotus n. sp. RS1 7088 MNRJ 31520 Lagoa dos Tropeiros, Brazil
Gymnotus n. sp. XING 7305 MNRJ 33642 Xingú-Tapajós, Brazil
Gymnotus obscurus 2017 MZUSP 75155 Lago Mamirauá, Brazil
Gymnotus obscurus 2018 MZUSP 75157 Lago Mamirauá, Brazil
Gymnotus omarorum 7092 No Voucher Uruguay
Gymnotus omarorum 7093 No Voucher Uruguay
Gymnotus panamensis 8018 STRI-7726 Rio Cricamola, Panama
Gymnotus panamensis 8021 ROM 89753 Rio Cricamola, Panama
Gymnotus panamensis 8210 STRI-01579 Rio Cricamola, Panama
Gymnotus pantanal 7076 No Voucher Parana, Argentina
Gymnotus pantherinus 2039 No Voucher Rio Perequê-Açu, Brazil
Gymnotus pantherinus 2945 No Voucher Rio Vermelho, Brazil
Gymnotus pantherinus 7111 MZUSP 87564 Rio Vermelho, Brazil
Gymnotus pedanopterus 2058 UF 174328 Rio Atabapo, Venezuela
Gymnotus pedanopterus 2059 UF 174328 Rio Atabapo, Venezuela
Gymnotus stenoleucus 2060 UF 174329 Rio Atabapo, Venezuela
Gymnotus stenoleucus 2061 UF 174331 Rio Cataniapo, Venezuela
Gymnotus stenoleucus 2064 UF 174329 Rio Atabapo, Venezuela
Gymnotus sylvius
7239 No Voucher
Rio Ribeira de Iguape-Rio Juqueia-Rio São Lourenço,
Brazil
Gymnotus sylvius
7240 No Voucher
Rio Ribeira de Iguape-Rio Juqueia-Rio São Lourenço,
Brazil
Gymnotus tigre 7349 No Voucher Aquarium
Gymnotus tigre 7090 No Voucher Aquarium
Gymnotus ucamara 1927 UF 126184 Rio Ucayali, Peru
Gymnotus ucamara 1950 UF 126184 Rio Ucayali, Peru
Gymnotus varzea 2014 MZUSP 75163 Rio Solimões, Brazil
Gymnotus varzea 2015 MZUSP 75164 Rio Solimões, Brazil
Hypopomus artedi 2232 ANSP 179505 Mazaruni River, Guyana
Rhamphichthys rostratus 2632 UF 116575 Rio Amazonas, Peru
Sternopygus astrabes 2203 No Voucher Lago Tefé, Brazil
Sternopygus macrurus 2639 UF 117121 Rio Nanay, Peru
a Drainage abbreviations: OR, Orinoco; CA, Central Amazon; WA, Western Amazon; GU, Guyanas.
56
Table 2. List of primers used for amplification and sequencing of the cyt b, 16S, RAG2, and Zic1 genes.
Primer Name Primer Sequence (5’–3’) Source
GLUDG.L CGAAGCTTGACTTGAARAACCAYCGTTG Palumbi et al. 1991
CytbR (CB6THR-H) CTCCGATCTTCGGATTACAAG Palumbi et al. 1991
H15573 AATAGGAAGTATCATTCGGGTTTGATG Meyer 1993
16Sar CGCCTGTTTATCAAAAACAT Palumbi 1996
16Sbr CCGGTCTGAACTCAGATCACGT Palumbi 1996
RAG2F1 TTTGGRCARAAGGGCTGGCC Lovejoy and Collette 2001
RAG2R6 TGRTCCARGCAGAAGTACTTG Lovejoy and Collette 2001
RAG2GYF ACAGGCATCTTTGGKATTCG Lovejoy et al. 2010
RAG2GYR TCATCCTCCTCATCTTCCTC Lovejoy et al. 2010
Zic1_F9 GGACGCAGGACCGCARTAYC Li et al. 2007
Zic1_R967 CTGTGTGTGTCCTTTTGTGRATYTT Li et al. 2007
Zic1_intF TCCTCGAACGTGGTGAACAG This study
Zic1_intR TTCGGGTTAGTTAGTTGCTCCGG This study
57
Table 3. Summary of EOD recordings.
Species Specimen EOD Temperature
(°C)
Conductivity
(µScm-1
)
Drainage Basin
Gymnotus panamensis 8015 2010-02-18-15 26.8 54.9 Cricamola, Panama
Gymnotus panamensis 8016 2010-02-18-16 27.2 56.2 Cricamola, Panama
Gymnotus panamensis 8017 2010-02-18-17 27.2 56.7 Cricamola, Panama
Gymnotus panamensis 8018 2010-02-18-18 27 59.2 Cricamola, Panama
Gymnotus panamensis 8019 2010-02-18-19 27.1 56.5 Cricamola, Panama
Gymnotus panamensis 8021 2010-02-18-21 27.2 56.6 Cricamola, Panama
Gymnotus panamensis 8022 2010-02-18-22 27.2 56.5 Cricamola, Panama
Gymnotus panamensis 8023 2010-02-18-23 27.2 56.7 Cricamola, Panama
Gymnotus maculosus 8119 2010-04-20-119 26.8 49.5 Bebedero, Costa Rica
Gymnotus maculosus 8120 2010-04-20-120 27 49.1 Bebedero, Costa Rica
Gymnotus maculosus 8121 2010-04-20-121 26.8 51.2 Bebedero, Costa Rica
Gymnotus maculosus 8122 2010-04-20-122 26.8 51.1 Bebedero, Costa Rica
Gymnotus maculosus 8123 2010-04-20-123 26.8 51.1 Bebedero, Costa Rica
Gymnotus maculosus 8124 2010-04-20-124 26.8 51.3 Bebedero, Costa Rica
Gymnotus maculosus 8125 2010-04-20-125 26.9 48.8 Bebedero, Costa Rica
Gymnotus maculosus 8126 2010-04-20-126 26.9 49.3 Bebedero, Costa Rica
Gymnotus maculosus 8127 2010-04-20-127 26.8 49.8 Bebedero, Costa Rica
Gymnotus maculosus 8128 2010-04-20-128 26.9 49.1 Bebedero, Costa Rica
Gymnotus maculosus 8129 2010-04-20-129 26.8 51.3 Bebedero, Costa Rica
Gymnotus maculosus 8130 2010-04-20-130 26.8 51.3 Bebedero, Costa Rica
Gymnotus maculosus 8131 2010-04-20-131 26.8 49.3 Bebedero, Costa Rica
Gymnotus maculosus 8132 2010-04-20-132 26.8 51 Bebedero, Costa Rica
Gymnotus maculosus 8133 2010-04-20-133 27 47.7 Bebedero, Costa Rica
Gymnotus maculosus 8134 2010-04-20-134 26.8 50.5 Bebedero, Costa Rica
Gymnotus maculosus 8135 2010-04-20-135 26.8 49.6 Bebedero, Costa Rica
Gymnotus maculosus 8136 2010-04-20-136 26.8 49.3 Bebedero, Costa Rica
Gymnotus maculosus 8137 2010-04-22-137 27.2 59.8 Bebedero, Costa Rica
Gymnotus maculosus 8138 2010-04-22-138 27.2 59.7 Bebedero, Costa Rica
Gymnotus maculosus 8139 2010-04-22-139 27.2 59.6 Bebedero, Costa Rica
Gymnotus maculosus 8140 2010-04-22-140 27.2 59.9 Bebedero, Costa Rica
Gymnotus maculosus 8141 2010-04-22-141 27.2 60 Bebedero, Costa Rica
Gymnotus maculosus 8142 2010-04-22-142 27.2 59.9 Bebedero, Costa Rica
Gymnotus maculosus 8143 2010-04-22-143 27.1 59.7 Bebedero, Costa Rica
Gymnotus maculosus 8144 2010-04-22-144 27.2 59.6 Bebedero, Costa Rica
Gymnotus maculosus 8145 2010-04-22-145 27.2 59.6 Bebedero, Costa Rica
Gymnotus maculosus 8146 2010-04-22-146 27.1 59.8 Bebedero, Costa Rica
Gymnotus maculosus 8147 2010-04-22-147 27.2 60 Bebedero, Costa Rica
Gymnotus maculosus 8148 2010-04-22-148 27.2 59.5 Bebedero, Costa Rica
Gymnotus cylindricus 8149 2010-04-22-149 27.2 59.5 Lake Arenal, Costa Rica
Gymnotus cylindricus 8150 2010-04-22-150 26.9 59.7 Lake Arenal, Costa Rica
Gymnotus cylindricus 8151 2010-04-22-151 27.2 59.5 Lake Arenal, Costa Rica
Gymnotus cylindricus 8152 2010-04-22-152 27 59.6 Lake Arenal, Costa Rica
Gymnotus cylindricus 8153 2010-04-22-153 26.9 59.4 Lake Arenal, Costa Rica
Gymnotus cylindricus 8154 2010-04-22-154 27.2 59.5 Lake Arenal, Costa Rica
Gymnotus cylindricus 8155 2010-04-23-155 26.9 65.8 San Carlos, Costa Rica
Gymnotus cylindricus 8156 2010-04-23-156 26.9 65.7 San Carlos, Costa Rica
Gymnotus cylindricus 8157 2010-04-23-157 26.9 65.7 San Carlos, Costa Rica
Gymnotus cylindricus 8158 2010-04-23-158 26.8 65.9 San Carlos, Costa Rica
Gymnotus cylindricus 8159 2010-04-23-159 26.8 65.9 San Carlos, Costa Rica
Gymnotus cylindricus 8160 2010-04-24-160 26.9 65.8 Bebedero, Costa Rica
58
Gymnotus cylindricus 8161 2010-04-24-161 26.8 66.3 Bebedero, Costa Rica
Gymnotus cylindricus 8162 2010-04-24-162 26.9 66.1 Bebedero, Costa Rica
Gymnotus cylindricus 8163 2010-04-24-163 26.9 66.3 Bebedero, Costa Rica
Gymnotus cylindricus 8164 2010-04-24-164 26.9 66.7 Bebedero, Costa Rica
Gymnotus cylindricus 8165 2010-04-24-165 26.9 66.5 Bebedero, Costa Rica
Gymnotus cylindricus 8166 2010-04-24-166 26.8 66.9 Sarapiquí, Costa Rica
Gymnotus maculosus 8167 2010-04-25-167 26.8 68.6 Tempisque, Costa Rica
Gymnotus maculosus 8168 2010-04-25-168 26.8 68.6 Tempisque, Costa Rica
Gymnotus maculosus 8169 2010-04-25-169 26.8 68.6 Tempisque, Costa Rica
Gymnotus ardilai 8172 2010-06-14-172 26.7 126.6 Magdalena, Colombia
Gymnotus ardilai 8173 2010-06-14-173 26.2 122 Magdalena, Colombia
Gymnotus ardilai 8174 2010-06-14-174 26.2 153.4 Magdalena, Colombia
Gymnotus ardilai 8175 2010-06-15-175 26.8 122.9 Magdalena, Colombia
Gymnotus ardilai 8179 2010-06-16-179 27.9 113.4 Magdalena, Colombia
Gymnotus ardilai 8180 2010-06-16-180 28.2 113.3 Magdalena, Colombia
Gymnotus ardilai 8181 2010-06-16-181 26.7 112 Magdalena, Colombia
Gymnotus ardilai 8182 2010-06-17-182 27.2 153.2 Magdalena, Colombia
Gymnotus ardilai 8183 2010-06-17-183 27 152.8 Magdalena, Colombia
Gymnotus ardilai 8184 2010-06-17-184 27.2 129.8 Magdalena, Colombia
Gymnotus ardilai 8185 2010-06-17-185 27.1 130.1 Magdalena, Colombia
Gymnotus ardilai 8186 2010-06-17-186 27 153 Magdalena, Colombia
Gymnotus henni 8187 2010-06-23-187 27.2 52.9 Dagua, Colombia
Gymnotus henni 8188 2010-06-23-188 27.1 53.2 Dagua, Colombia
Gymnotus henni 8189 2010-06-23-189 27.1 53.1 Dagua, Colombia
Gymnotus henni 8191 2010-06-23-191 27.1 53.5 Dagua, Colombia
Gymnotus henni 8193 2010-06-23-193 27 53.6 Dagua, Colombia
59
Figure 1: Family level relationships of the order Gymnotiformes after Stoddard (2002a).
60
Figure 2: Geographic distribution of gymnotiform species with delineation of biogeographic regions. Modified from
Albert et al. (2004). Distribution in the trans-Andean region is shaded in red, and in the cis-Andean region in blue.
Abbreviations: EA, Amazon Basin east of Purus Arch and all tributaries below fall-line of Guyana Shield (2 985 000
km2). GU, Guyanas – Orinoco Basin, including island of Trinidad and Upper Negro drainages above fall line (1 843
000 km2). MA, Atlantic and Pacific slopes of Middle America from the Motagua to Tuyra Basins (393 000 km2).
NE, coastal drainages of northeast Brazil including Parnaíba, Piaui, São Francisco and Jequitinhonha Basins (1 357
000 km2). NW, Northwestern South America including the Magdalena and Maracaibo Basins, and the north slope of
Venezuela (471 000 km2). PA, Paraguay-Paraná Basin including Dulce-Salí and Salado Basins of Argentina (3 185
000 km2). PS, Pacific Slope of Colombia and Ecuador, from Baudó to Guayaquil Basins, including the Atrato
(Caribbean) Basin (200 000 km2). SE, coastal drainages of southeast Brazil and Uruguay from the Docé to Lagoa
Mirim Basins (628 000 km2). WA, Amazon Basin west of Purus Arch, below about 500 m elevation (3 556 000
km2).
61
Figure 3: Type-locality map for 35 described Gymnotus species modified from Albert et al. (2004).
62
Figure 4: Distribution map for trans-Andean Gymnotus species. Arrows indicate position of highly localized
distributions.
63
Figure 5: Morphological Hypothesis for Gymnotus after Albert et al. (2004). Trans-Andean Gymnotus species are
shown in red.
64
Figure 6: Molecular Hypothesis for Gymnotus after Lovejoy et al. (2010). Trans-Andean Gymnotus species are
shown in red.
65
Figure 7: Electrostatic field of Gymnotiformes after Stoddard (2002a). The blue circle represents a resistive object,
which diverts the electric field and the red circle represents a conductive object which concentrates the electric field.
The green portion on the fish represents the bilateral pair of electric organs that extend along the ventral portion of
the body.
66
Figure 8: Spectral sensitivity of the two types of electroreceptor cells in Gymnotiformes after Stoddard (2002a).
67
Figure 9: Pulse and Wave type signal discharges after Stoddard and Markham (2008). On the left, the waveforms are
represented in voltage over time. On the right are examples of power spectra for the corresponding signal type. Pulse
type discharges are characterized by one to six phases (i.e. deviations from the 0V baseline) of alternating polarity
punctuated by brief periods of silence. In contrast, wave type discharges are characterized by a pattern of one to four
phases recurring in a continuous cycle.
68
Figure 10: Voltage-time waveforms of monophasic and multiphasic signals modified from Stoddard (2002b).
69
Figure 11: Electric organ discharge production after Stoddard (2002a). Electrocytes are arranged within tubes placed
in series to sum the voltage and the tubes are stacked in parallel to sum the current. A) An action potential causes
depolarization of the caudal face of the electrocyte, which causes sodium ions to flow towards the anterior portion of
the electric organ. This results in the head-positive first phase of the EOD. B) This current triggers a second action
potential in the rostral face of the electrocyte, causing sodium ions to flow towards the posterior portion of the
electric signal. This results in the head-negative second phase of the EOD. C) When both faces depolarize in
sequence, a biphasic signal is the result. Triggering of accessory electric organs and specialized electrocytes is
responsible for the production of additional phases.
70
Figure 12: Voltage/time waveform of both the first phase and the full EOD of Brachyhypopomus pinnicaudatus and
their corresponding power spectrum plotted over the spectral sensitivity of ampullary electroreceptors. Modified
from Stoddard (2002b). All known electroreceptive predators possess ampullary electroreceptors that are maximally
sensitive around 30Hz. The full EOD waveform has much less energy in the range of the ampullary receptors.
Multiphasic signals should be relatively cryptic to electroreceptive predators.
71
Figure 13: Collecting localities in Panama and Costa Rica. Blue pins represent localities for G. cylindricus, yellow
pins represent localities for G. maculosus, and the green pin represents the locality for G. panamensis.
72
Figure 14: Collecting localities in Colombia. The red pin represents the locality for G. henni and the white pin
represents the localities for G. ardilai.
73
Figure 15: Strict consensus phylogeny of 422 most parsimonious trees showing Gymnotus relationships, based on
the combined analysis of cyt b, 16S, RAG2, and Zic1 genes (3807 characters, 5037 steps, CI=0.47, RI=0.85).
Numbers above nodes represent bootstrap values. Trans-Andean Gymnotus species are shown in red.
74
Figure 16: Maximum Likelihood phylogeny showing Gymnotus relationships, based on the combined analysis of cyt
b, 16S, RAG2, and Zic1 genes. Numbers above nodes represent bootstrap values. Trans-Andean Gymnotus species
are shown in red.
75
Figure 17: Bayesian phylogeny showing Gymnotus relationships, based on the combined analysis of cyt b, 16S,
RAG2, and Zic1 genes. Numbers above nodes represent posterior probabilities. Trans-Andean Gymnotus species are
shown in red.
76
Figure 18: Results of Maximum Parsimony analyses of individual mtDNA and RAG2 datasets. The strict consensus
tree of Zic1 was not sufficiently resolved and is not shown. Redundant individuals of the same species have been
pruned from the trees. Trans-Andean Gymnotus species are shown in red.
77
Figure 19: Results of Maximum Likelihood analyses of individual mtDNA, RAG2, and Zic1 datasets. Redundant
individuals of the same species have been pruned from the trees. Trans-Andean Gymnotus species are shown in red.
78
Figure 20: Electric organ discharges of five species of trans-Andean Gymnotus visualized as voltage over time
waveforms.
79
Figure 21: Maximum Likelihood Optimization of electric organ discharge (EOD) phase number of Gymnotus
species using the total evidence Maximum Likelihood consensus phylogeny. Ancestral state reconstructions are
represented as proportional likelihoods. Trans-Andean Gymnotus species are shown in red.
80
Figure 22: Parsimony Optimization of electric organ discharge (EOD) phase number of Gymnotus species using the
total evidence Maximum Likelihood consensus phylogeny. Ancestral states were assessed from eight equally
parsimonious reconstructions. Ancestral states are shown above the equivocal nodes in proportion to their
appearance in the eight trees. Trans-Andean Gymnotus species are shown in red. Note that this tree shows the most
parsimonious character state reconstruction for the unknown EODs of G. n. sp. XING, G. bahianus, G. choco, G. n.
sp. RSI.
81
Appendices
Appendix A: 16S Alignment.
FORMAT DATATYPE = DNA INTERLEAVE GAP = - MISSING = ?;
MATRIX
Brachyhypopomus_brevirostris_2617 -------------------------------------GAGGTCCCGCCTGCCCAGTGAC-
Brachyhypopomus_diazi_2408 -----------------------------------AGGAGGTCCCGCCTGCCCAGTGAC-
Brachyhypopomus_diazi_305 ---------------------------------------------------CCAGTGAC-
Brachyhypopomus_n._sp._PAL_2432 -------------------------------------GAGGTCCCGCCTGCCCAGTGAC-
Electrophorus_electricus_2026 --------------CTTCTGT---AACCTATATATAGGAGGTCCTGCCTGCCCAGTGAA-
Electrophorus_electricus_2619 ---AAAAACATCGCCTTCTGT---AACCTATATATAGGAGGTCCTGCCTGCCCAGTGAA-
Gymnotus_aff._anguillaris_2091 ----------------------------AGTACATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_arapaima_2002 -------------------------------------GAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_arapaima_2003 ------------------------------------------------------------
Gymnotus_ardilai_8175 ---AAAAACATCGCCTCCCGC--AAATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_ardilai_8186 --CAAAAACATCGCCTCCCGC--AAATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_bahianus_7244 --CAAAAACATCGCCTCCCGC--AAATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_bahianus_7245 --CAAAAACATCGCCTCTCGC--AAATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_carapo_(CA)_2004 ---AAAAACATCGCCTCCCGC--AAATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_carapo_(CA)_2030 ------------------------AATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_carapo_(OR)_2040 -----------------------------ATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_carapo_(OR)_2041 -----------------------------ATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_carapo_(WA)_2006 ------------------------AATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_carapo_(WA)_2007 ------------------------AATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_cataniapo_2062 ------------------------AACACACACATAGGAGGTCCTGCCTGCCCGGTGAC-
Gymnotus_cataniapo_2063 ----AAAACATCGCCTCCCGC--AAACACACACATAGGAGGTCCTGCCTGCCCGGTGAC-
Gymnotus_chaviro_7357 ----AAAACATCGCCTCCCGC--AAATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_chaviro_7358 ---------------------------------------------------CCAGTGAC-
Gymnotus_choco_8209 -------------------------------------GAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_coatesi_2042 ------AACATCGCCTCTTGC--AAATTAATACATAAGAGGTCCTGCCTGCCCGGTGACG
Gymnotus_coatesi_2043 ---------------TCTTGC--AAATTAATACATAAGAGGTCCTGCCTGCCCGGTGACG
Gymnotus_coropinae_(CA)_2010 -------------------------ATTAATACATAAGAGGTCCTGCCTGCCCGGTGACG
Gymnotus_coropinae_(CA)_2025 ---------------TCTTGC--AAATTAATACATAAGAGGTCCTGCCTGCCCGGTGACG
Gymnotus_coropinae_(GU)_2035 -----------------TTGC--AAGTTA-CACATAAGAGGTCCTGCCTGCCCGGTGACG
Gymnotus_coropinae_(GU)_2036 -------------------------AGTTACACATAAGAGGTCCTGCCTGCCCGGTGACG
Gymnotus_coropinae_(GU)_2037 -------------------------AGTTACACATAAGAGGTCCTGCCTGCCCGGTGACG
Gymnotus_coropinae_(GU)_2038 -----------------------------ACACATAAGAGGTCCTGCCTGCCCGGTGACG
Gymnotus_curupira_2009 ---AAAAACATCGCCTCCCGC--AAATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_curupira_2019 ------------------------------------GGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_curupira_2021 ---AAAAACATCGCCTCCCGC--AAATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_curupira_2024 ----AAAACATCGCCTCCCGC--AAATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_cylindricus_2092 ------------------------------------GGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_cylindricus_2093 ------------------------------------GGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_cylindricus_2094 ------------------------------------GGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_henni_7276 --CAAAAACATCGCCTCCCGA--AAATCAACACATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_henni_7277 --CAAAAACATCGCCTCCCGA--AAATCAACACATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_henni_8189 ---AAAAACATCGCCTCCCGA--AAATCAACACATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_henni_8193 ---AAAAACATCGCCTCCCGA--AAATCAACACATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_henni_8207 ---AAAAACATCGCCTCCCGC--AAATCAATACATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_henni_8230 --CAAAAACATCGCCTCCCGA--AAATCAACACATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_henni_8231 --CAAAAACATCGCCTCCCGA--AAATCAACACATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_javari_2020 ---------------------------------------GGTCCTGCCTGCCCGGTGACG
Gymnotus_jonasi_2016 -----------------------------ACACAT-AGAGGTCCTGCCTGCCCAGTGACA
Gymnotus_jonasi_2471 ---------------------------------------GGTCCTGCCTGCCCAGTGACA
Gymnotus_maculosus_8126 -------------------------------------GAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_maculosus_8137 -------------------------------------GAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_maculosus_8169 -------------------------------------GAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_maculosus_8213 -------------------------------------GAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_mamiraua_2012 ------------------------AA-TAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_mamiraua_2013 ATCA-AAACATCGCCTCCCGC--AAATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_n._sp._7104 --CAAAAACATCGCCTCCCGC--AAATTAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_n._sp._7105 --CAAAAACATCGCCTCCCGC--AAATTAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_n._sp._CORU_2558 -TCAAAAACATCGCCTCCCGC--AAATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_n._sp._FRIT_7109 ---AAAAACATCGCCTCCCGC--AAACTAACACATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_n._sp._ITAP_2559 -TCAAAAACATCGCCTCCCGC--AAATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_n._sp._ITAP_7071 ------------------------------------GGAGGTCCTGCCTGCCCAGTGAC-
82
Gymnotus_n._sp._ITAP_7072 --CAAAAACATCGCCTCCCGC--AAATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_n._sp._ITAP_7074 --CAAAAACATCGCCTCCCGC--AAATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_n._sp._ITAP_7075 --------------------C--AAATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_n._sp._MAMA_7065 ---AAAAACATCGCCTCCCGC--AAATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_n._sp._MAMA_7066 --CAAAAACATCGCCTCCCGC--AAATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_n._sp._MAMA_7067 ------------------------------------------CCTGCCTGCCCAGTGAC-
Gymnotus_n._sp._RS1_7088 -TCAAAAACATCGCCTCCCGC--AAATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_n._sp._XING_7305 ---AAAAACATCGCCTCCCGC---AATTAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_obscurus_2017 ATCAAAAACATCGCCTCCCGC--AAATCAATGTATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_obscurus_2018 ------------------------------------GGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_omarorum_7092 ---AAAAACATCGCCTCCCGC--AAATCAATACATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_omarorum_7093 ------------------------------------------CCTGCCTGCCCAGTGAC-
Gymnotus_panamensis_8018 --CAAAAACATCGCCTCCCGC--AAATTAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_panamensis_8021 ---AAAAACATCGCCTCCCGC--AAATTAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_panamensis_8210 ---AAAAACATCGCCTCCCGC--AAATTAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_pantanal_7076 -TCAAAAACATCGCCTCCCGC--AAATTAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_pantherinus_2039 ----------------------------AACACATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_pantherinus_2945 ---AAAAACATCGCCTCCTGC--AAA-TAACACATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_pantherinus_7111 --CAAAAACATCGCCTCCTGC--AAAT-AACACATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_pedanopterus_2058 -------------------------------------GAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_pedanopterus_2059 -------------------------------------GAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_stenoleucus_2060 ------AACATCGCCTCTTGC--AAATTAACACATAAGAGGTCCTGCCTGCCCGGTGACG
Gymnotus_stenoleucus_2061 --------------CTCTTG----AATTAACACATAAGAGGTCCTGCCTGCCCGGTGACG
Gymnotus_stenoleucus_2064 ------------------------AATTAACACATAAGAGGTCCTGCCTGCCCGGTGACG
Gymnotus_sylvius_7239 ---AAAAACATCGCCTCCCGC--AAATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_sylvius_7240 ---AAAAACATCGCCTCCCGC--AAATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_tigre_7090 --CAAAAACATCGCCTCCCGC--AAACCAGTATATGGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_tigre_7349 -TCAAAAACATCGCCTCCCGC--AAACCAGTATATGGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_ucamara_1927 ---AAAAACATCGCCTCCCGC--AAATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_ucamara_1950 ----------------CCCGC--AAATCAATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_varzea_2014 ----------------------------AATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Gymnotus_varzea_2015 -----------------------------ATATATAGGAGGTCCTGCCTGCCCAGTGAC-
Hypopomus_artedi_2232 -------------------------------------GAGGTCCCGCCTGCCCAGTGAC-
Rhamphichthys_rostratus_2632 -------------------------------------GAGGTCCTGCCTGCCCGGTGACT
Sternopygus_astrabes_2203 ---AAAAACATCGCCTCCCGCAAAACTCAATGTATAGGAGGTCCTGCCTGCCCAGTGACT
Sternopygus_macrurus_2639 -----------------------AAATCAATGTATAGGAGGTCCTGCCTGCCCAGTGACT
Brachyhypopomus_brevirostris_2617 CACTGTTT-AACGGCCGCGGTATTTTAACCGTGCAAAGGTAGCGCAATCACTTGTCTTTT
Brachyhypopomus_diazi_2408 CACTGTTT-AACGGCCGCGGTATTTTAACCGTGCAAAGGTAGCGCAATCACTTGTCCTTT
Brachyhypopomus_diazi_305 CACTGTTT-AACGGCCGCGGTATTTTAACCGTGCAAAGGTAGCGCAATCACTTGTCCTTT
Brachyhypopomus_n._sp._PAL_2432 CCCTGTTC-AACGGCCGCGGTATTTTAACCGTGCAAAGGTAGCGCAATCACTTGTCCTTT
Electrophorus_electricus_2026 ---TATTA-AACGGCCGCGGTATTTTGACCGTGCAAAGGTAGCGCAATCACTTGCCCCTT
Electrophorus_electricus_2619 ---TATTA-AACGGCCGCGGTATTTTGACCGTGCAAAGGTAGCGCAATCACTTGCCCCTT
Gymnotus_aff._anguillaris_2091 AACAATTTTAACGGCCGCGGTATCCTGACCGTGCAAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_arapaima_2002 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_arapaima_2003 ----------------------TCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_ardilai_8175 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_ardilai_8186 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_bahianus_7244 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_bahianus_7245 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_carapo_(CA)_2004 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_carapo_(CA)_2030 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_carapo_(OR)_2040 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_carapo_(OR)_2041 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_carapo_(WA)_2006 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_carapo_(WA)_2007 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_cataniapo_2062 AACAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_cataniapo_2063 AACAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_chaviro_7357 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_chaviro_7358 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_choco_8209 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_coatesi_2042 AACAGTTC-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTCTT
Gymnotus_coatesi_2043 AACAGTTC-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTCTT
Gymnotus_coropinae_(CA)_2010 AACAGTTC-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTCTT
Gymnotus_coropinae_(CA)_2025 AACAGTTC-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTCTT
Gymnotus_coropinae_(GU)_2035 AACAGTTC-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTCTT
Gymnotus_coropinae_(GU)_2036 AACAGTTC-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTCTT
Gymnotus_coropinae_(GU)_2037 AACAGTTC-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTCTT
Gymnotus_coropinae_(GU)_2038 AACAGTTC-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTCTT
Gymnotus_curupira_2009 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_curupira_2019 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_curupira_2021 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_curupira_2024 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
83
Gymnotus_cylindricus_2092 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_cylindricus_2093 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_cylindricus_2094 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_henni_7276 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCAAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_henni_7277 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCAAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_henni_8189 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCAAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_henni_8193 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCAAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_henni_8207 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_henni_8230 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCAAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_henni_8231 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCAAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_javari_2020 AACAGTTC-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTCTT
Gymnotus_jonasi_2016 AATAGTTC-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTCTT
Gymnotus_jonasi_2471 AATAGTTC-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTCTT
Gymnotus_maculosus_8126 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_maculosus_8137 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_maculosus_8169 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_maculosus_8213 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_mamiraua_2012 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_mamiraua_2013 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_n._sp._7104 AACAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_n._sp._7105 AACAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_n._sp._CORU_2558 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_n._sp._FRIT_7109 AACTGTTT-AACGGCCGCGGTATCCTGACCGTGCAAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_n._sp._ITAP_2559 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_n._sp._ITAP_7071 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_n._sp._ITAP_7072 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_n._sp._ITAP_7074 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_n._sp._ITAP_7075 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_n._sp._MAMA_7065 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_n._sp._MAMA_7066 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_n._sp._MAMA_7067 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_n._sp._RS1_7088 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_n._sp._XING_7305 AACAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_obscurus_2017 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_obscurus_2018 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_omarorum_7092 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_omarorum_7093 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_panamensis_8018 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_panamensis_8021 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_panamensis_8210 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_pantanal_7076 AACAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_pantherinus_2039 AACAATTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_pantherinus_2945 AACAATTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_pantherinus_7111 AACAATTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_pedanopterus_2058 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCAAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_pedanopterus_2059 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCAAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_stenoleucus_2060 AATAGTTC-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTCTT
Gymnotus_stenoleucus_2061 AACAGTTC-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTCTT
Gymnotus_stenoleucus_2064 AACAGTTC-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTCTT
Gymnotus_sylvius_7239 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_sylvius_7240 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_tigre_7090 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCAAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_tigre_7349 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCAAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_ucamara_1927 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_ucamara_1950 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_varzea_2014 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Gymnotus_varzea_2015 AATAGTTT-AACGGCCGCGGTATCCTGACCGTGCGAAGGTAGCGCAATCACTTGTCTTTT
Hypopomus_artedi_2232 CACTGTTT-AACGGCCGCGGTATTTTAACCGTGCAAAGGTAGCGCAATCACTTGTCCTTT
Rhamphichthys_rostratus_2632 ATTAGTTT-AACGGCCGCGGTATTTTGACCGTGCAAAGGTAGCGCAATCACTTGTCCTTT
Sternopygus_astrabes_2203 GTCAGTTT-AACGGCCGCGGTATTTTGACCGTGCAAAGGTAGCGCAATCACTTGTCTTTT
Sternopygus_macrurus_2639 ATTAGTTT-AACGGCCGCGGTATTTTGACCGTGCAAAGGTAGCGCAATCACTTGTCTTTT
Brachyhypopomus_brevirostris_2617 AAATGAAGACCTGTATGAATGGCATAACGAGGGCTCTACTGTCTCCCCTTTCAAGTCAGT
Brachyhypopomus_diazi_2408 AAATGAAGACCTGTATGAATGGCATAACGAGGGCTTTACTGTCTCCCCTTTCAAGTCAGT
Brachyhypopomus_diazi_305 AAATGAAGACCTGTATGAATGGCATAACGAGGGCTTTACTGTCTCCCCTTTCAAGTCAGT
Brachyhypopomus_n._sp._PAL_2432 AAATGAAGACCTGTATGAATGGCATAACGAGGGCTTTACTGTCTCCCCTTTCAAGTCAGT
Electrophorus_electricus_2026 AATTAGGGGCCTGTATGAATGGCTAGACGAAGGCCCAACTGTCTCCCTTTTCAAATCAGT
Electrophorus_electricus_2619 AATTAGGGGCCTGTATGAATGGCTAGACGAAGGCCCAACTGTCTCCCTTTTCAAATCAGT
Gymnotus_aff._anguillaris_2091 AAATAAAGACCCGTATGAATGGCAAAACGAGGGCTTAGCTGTCTCCCTTTACAAGTCAGT
Gymnotus_arapaima_2002 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_arapaima_2003 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_ardilai_8175 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_ardilai_8186 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
84
Gymnotus_bahianus_7244 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_bahianus_7245 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_carapo_(CA)_2004 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_carapo_(CA)_2030 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_carapo_(OR)_2040 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_carapo_(OR)_2041 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_carapo_(WA)_2006 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_carapo_(WA)_2007 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_cataniapo_2062 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_cataniapo_2063 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_chaviro_7357 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_chaviro_7358 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_choco_8209 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_coatesi_2042 AAATAGGGACCTGTATGAATGGCAAAACGAAGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_coatesi_2043 AAATAGGGACCTGTATGAATGGCAAAACGAAGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_coropinae_(CA)_2010 AAATAGGGACCTGTATGAATGGCAAAACGAGGGCTTAGCTGTCTCCCTTTACAAGTCAGT
Gymnotus_coropinae_(CA)_2025 AAATAGGGACCTGTATGAATGGCAAAACGAGGGCTTAGCTGTCTCCCTTTACAAGTCAGT
Gymnotus_coropinae_(GU)_2035 AAATAGGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_coropinae_(GU)_2036 AAATAGGGACCTGTATGAATGGCAAAACGAGGGCTTAGCTGTCTCCCTTTACAAGTCAGT
Gymnotus_coropinae_(GU)_2037 AAATAGGGACCTGTATGAATGGCAAAACGAGGGCTTAGCTGTCTCCCTTTACAAGTCAGT
Gymnotus_coropinae_(GU)_2038 AAATAGGGACCTGTATGAATGGCAAAACGAGGGCTTAGCTGTCTCCCTTTACAAGTCAGT
Gymnotus_curupira_2009 AAATAAAGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_curupira_2019 AAATAAAGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_curupira_2021 AAATAAAGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_curupira_2024 AAATAAAGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_cylindricus_2092 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAAT
Gymnotus_cylindricus_2093 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAAT
Gymnotus_cylindricus_2094 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAAT
Gymnotus_henni_7276 AAATAAAGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACTAGTCAAT
Gymnotus_henni_7277 AAATAAAGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACTAGTCAAT
Gymnotus_henni_8189 AAATAAAGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACTAGTCAAT
Gymnotus_henni_8193 AAATAAAGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACTAGTCAAT
Gymnotus_henni_8207 AAATAAAGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACTAGTCAAT
Gymnotus_henni_8230 AAATAAAGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACTAGTCAAT
Gymnotus_henni_8231 AAATAAAGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACTAGTCAAT
Gymnotus_javari_2020 AAATAGGGACCTGTATGAATGGCAAAACGAAGGCTTAGCTGTCTCCCTTTACAAGTCAGT
Gymnotus_jonasi_2016 AAATAGAGACCTGTATGAATGGCAAAACGAGGGCTTAGCTGTCTCCCTTTACAAGTCAGT
Gymnotus_jonasi_2471 AAATAGAGACCTGTATGAATGGCAAAACGAGGGCTTAGCTGTCTCCCTTTACAAGTCAGT
Gymnotus_maculosus_8126 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAAT
Gymnotus_maculosus_8137 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAAT
Gymnotus_maculosus_8169 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAAT
Gymnotus_maculosus_8213 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAAT
Gymnotus_mamiraua_2012 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_mamiraua_2013 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_n._sp._7104 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_n._sp._7105 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_n._sp._CORU_2558 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_n._sp._FRIT_7109 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_n._sp._ITAP_2559 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_n._sp._ITAP_7071 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_n._sp._ITAP_7072 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_n._sp._ITAP_7074 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_n._sp._ITAP_7075 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_n._sp._MAMA_7065 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_n._sp._MAMA_7066 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_n._sp._MAMA_7067 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_n._sp._RS1_7088 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_n._sp._XING_7305 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_obscurus_2017 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_obscurus_2018 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_omarorum_7092 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_omarorum_7093 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_panamensis_8018 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAAT
Gymnotus_panamensis_8021 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAAT
Gymnotus_panamensis_8210 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAAT
Gymnotus_pantanal_7076 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_pantherinus_2039 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTTCAAGTCAGT
Gymnotus_pantherinus_2945 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTTCAAGTCAGT
Gymnotus_pantherinus_7111 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTTCAAGTCAGT
Gymnotus_pedanopterus_2058 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
ymnotus_pedanopterus_2059 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_stenoleucus_2060 AAATAGGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_stenoleucus_2061 AAATAGGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
85
Gymnotus_stenoleucus_2064 AAATAGGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_sylvius_7239 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_sylvius_7240 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_tigre_7090 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACCAGTCAGT
Gymnotus_tigre_7349 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACCAGTCAGT
Gymnotus_ucamara_1927 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_ucamara_1950 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_varzea_2014 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Gymnotus_varzea_2015 AAATAAGGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCTTTACAAGTCAGT
Hypopomus_artedi_2232 AAATGAGGACCTGTATGAATGGCACCACGAGGGCTTTACTGTCTCCCTTTTCAAGTCAGT
Rhamphichthys_rostratus_2632 AAATGAGGACCTGTATGAAAGGCAAAACGAGGGCTTTACTGTCTCCCCATTCAAGTCAGT
Sternopygus_astrabes_2203 AAATGAAGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCCTCTCCAGTCAGT
Sternopygus_macrurus_2639 AAATGAAGACCTGTATGAATGGCAAAACGAGGGCTTAACTGTCTCCCCTTTCCAGTCAAT
Brachyhypopomus_brevirostris_2617 GAAATTGATCTGCCCGTGCAGAAGCGGACATAAAAATATAAGACGAGAAGACCCTTTGGA
Brachyhypopomus_diazi_2408 GAAATTGATCTGCCCGTGCAGAAGCGGACATAAAAATATAAGACGAGAAGACCCTTTGGA
Brachyhypopomus_diazi_305 GAAATTGATCTGCCCGTGCAGAAGCGGACATAAAAATATAAGACGAGAAGACCCTTTGGA
Brachyhypopomus_n._sp._PAL_2432 GAAATTGATCTGCCCGTGCAGAAGCGAGCATAAGAATATAAGACGAGAAGACCCTTTGGA
Electrophorus_electricus_2026 TAAATTGATCTACCCGTGCAGAAGCAGGTATTCACCTACAAGACGAGAAGACCCTTTGGA
Electrophorus_electricus_2619 TAAATTGATCTACCCGTGCAGAAGCAGGTATTCACCTACAAGACGAGAAGACCCTTTGGA
Gymnotus_aff._anguillaris_2091 GAAATTGACCTGTCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_arapaima_2002 GAAATTGACCTGCCCGTGCAGATGCGGGCATAACAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_arapaima_2003 GAAATTGACCTGCCCGTGCAGATGCGGGCATAACAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_ardilai_8175 GAAATTGACCTGCCCGTGCAGATGCGGACATAACAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_ardilai_8186 GAAATTGACCTGCCCGTGCAGATGCGGACATAACAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_bahianus_7244 GAAATTGACCTGCCCGTGCAGATGCGGGCATAACAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_bahianus_7245 GAAATTGACCTGCCCGTGCAGATGCGGGCATAACAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_carapo_(CA)_2004 GAAATTGACCTGCCCGTGCAGATGCGGGCATAACAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_carapo_(CA)_2030 GAAATTGACCTGCCCGTGCAGATGCGGGCATAACAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_carapo_(OR)_2040 GAAATTGACCTGCCCGTGCAGATGCGGACATAACAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_carapo_(OR)_2041 GAAATTGACCTGCCCGTGCAGATGCGGACATAACAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_carapo_(WA)_2006 GAAATTGACCTGCCCGTGCAGATGCGGGCATAACAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_carapo_(WA)_2007 GAAATTGACCTGCCCGTGCAGATGCGGGCATAACAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_cataniapo_2062 GAAATTGACCTGCCCGTGCAGATGCGGGCATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_cataniapo_2063 GAAATTGACCTGCCCGTGCAGATGCGGGCATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_chaviro_7357 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_chaviro_7358 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_choco_8209 GAAATTGACCTGCCCGTGCAGATGCGGACATAACAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_coatesi_2042 GAAATTGACCTGCCCGTGCAGATGCGGGCACAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_coatesi_2043 GAAATTGACCTGCCCGTGCAGATGCGGGCACAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_coropinae_(CA)_2010 GAAATTGACCTGCCCGTGCAGATGCGGGCACAATATTACAAGACGAGAAGACCCTTTGGA
Gymnotus_coropinae_(CA)_2025 GAAATTGACCTGCCCGTGCAGATGCGGGCACAATATTACAAGACGAGAAGACCCTTTGGA
Gymnotus_coropinae_(GU)_2035 GAAATTGACCTGCCCGTGCAGATGCGGGCACAATAGTACAAGACGAGAAGACCCTTTGGA
Gymnotus_coropinae_(GU)_2036 GAAATTGATCTGCCCGTGCAGATGCGGGCACAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_coropinae_(GU)_2037 GAAATTGACCTGCCCGTGCAGATGCGGGCACAATAGTACAAGACGAGAAGACCCTTTGGA
Gymnotus_coropinae_(GU)_2038 GAAATTGACCTGCCCGTGCAGATGCGGGCACAATAGTACAAGACGAGAAGACCCTTTGGA
Gymnotus_curupira_2009 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_curupira_2019 GAAATTGACCTGCCCGTGCAGATGCGGGCATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_curupira_2021 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_curupira_2024 GAAATTGACCTGCCCGTGCAGATGCGGGCATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_cylindricus_2092 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_cylindricus_2093 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_cylindricus_2094 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_henni_7276 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_henni_7277 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_henni_8189 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_henni_8193 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_henni_8207 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_henni_8230 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_henni_8231 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_javari_2020 GAAATTGACCTGCCCGTGCAGATGCGGGCACAATGATACAAGACGAGAAGACCCTTTGGA
Gymnotus_jonasi_2016 GAAATTGACCTGCCCGTGCAGATGCGGGCACAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_jonasi_2471 GAAATTGACCTGCCCGTGCAGATGCGGGCACAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_maculosus_8126 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_maculosus_8137 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_maculosus_8169 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_maculosus_8213 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_mamiraua_2012 GAAATTGACCTGCCCGTGCAGATGCGGGCATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_mamiraua_2013 GAAATTGACCTGCCCGTGCAGATGCGGGCATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_n._sp._7104 GAAATTGACCTGCCCGTGCAGATGCGGGCATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_n._sp._7105 GAAATTGACCTGCCCGTGCAGATGCGGGCATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_n._sp._CORU_2558 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_n._sp._FRIT_7109 GAAATTGACCTGCCCGTGCAGATGCGGGCATAATAATACAAGACGAGAAGACCCTTTGGA
86
Gymnotus_n._sp._ITAP_2559 GAAATTGACCTGCCCGTGCAGATGCGGGCATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_n._sp._ITAP_7071 GAAATTGACCTGCCCGTGCAGATGCGGGCATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_n._sp._ITAP_7072 GAAATTGACCTGCCCGTGCAGATGCGGGCATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_n._sp._ITAP_7074 GAAATTGACCTGCCCGTGCAGATGCGGGCATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_n._sp._ITAP_7075 GAAATTGACCTGCCCGTGCAGATGCGGGCATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_n._sp._MAMA_7065 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_n._sp._MAMA_7066 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_n._sp._MAMA_7067 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGAC-AGAAGACCCTTTGGA
Gymnotus_n._sp._RS1_7088 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_n._sp._XING_7305 GAAATTGACCTGCCCGTGCAGATGCGGGCATAATATTACAAGACGAGAAGACCCTTTGGA
Gymnotus_obscurus_2017 GAAATTGACCTGCCCGTGCAGATGCGGGCATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_obscurus_2018 GAAATTGACCTGCCCGTGCAGATGCGGGCATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_omarorum_7092 GAAATTGACCTGCCCGTGCAGATGCGGGCATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_omarorum_7093 GAAATTGACCTGCCCGTGCAGATGCGGGCATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_panamensis_8018 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_panamensis_8021 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_panamensis_8210 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_pantanal_7076 GAAATTGACCTGCCCGTGCAGATGCGGGCATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_pantherinus_2039 GAAATTGACCTGCCCGTGCAGATGCGGACATGATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_pantherinus_2945 GAAATTGACCTGCCCGTGCAGATGCGGACATGATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_pantherinus_7111 GAAATTGACCTGCCCGTGCAGATGCGGACATGATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_pedanopterus_2058 GAAATTGACCTGCCCGTGCAGATGCGGGCATAACAATACAAGACGAGAAGACCCTATGGA
Gymnotus_pedanopterus_2059 GAAATTGACCTGCCCGTGCAGATGCGGGCATAACAATACAAGACGAGAAGACCCTATGGA
Gymnotus_stenoleucus_2060 GAAATTGACCTGCCCGTGCAGATGCGGGCACAATTATACAAGACGAGAAGACCCTTTGGA
Gymnotus_stenoleucus_2061 GAAATTGACCTGCCCGTGCAGATGCGGGCACAATTATACAAGACGAGAAGACCCTTTGGA
Gymnotus_stenoleucus_2064 GAAATTGACCTGCCCGTGCAGATGCGGGCACAATTATACAAGACGAGAAGACCCTTTGGA
Gymnotus_sylvius_7239 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_sylvius_7240 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_tigre_7090 GAAATTGACCTGCCCGTGCAGATGCGGGCATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_tigre_7349 GAAATTGACCTGCCCGTGCAGATGCGGGCATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_ucamara_1927 GAAATTGACCTGCCCGTGCAGATGCGGGCATAACAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_ucamara_1950 GAAATTGACCTGCCCGTGCAGATGCGGGCATAACAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_varzea_2014 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Gymnotus_varzea_2015 GAAATTGACCTGCCCGTGCAGATGCGGACATAATAATACAAGACGAGAAGACCCTTTGGA
Hypopomus_artedi_2232 GAAATTGATCTGCCCGTGCAGAAGCGGACATAAAAATATAAGACGAGAAGACCCTTTGGA
Rhamphichthys_rostratus_2632 GAAATTGATCTGCCCGTGCAGAAGCGGACATAATTATACAAGACGAGAAGACCCTTTGGA
Sternopygus_astrabes_2203 GAAATTGATCTACCCGTGCAGAAGCGGGTATAAAGATACAAGACGAGAAGACCCTTTGGA
Sternopygus_macrurus_2639 GAAATTGATCTACCCGTGCAGAAGCGGGTATAAAAATACAAGACGAGAAGACCCTTTGGA
Brachyhypopomus_brevirostris_2617 GCTTAAGATAT-AAGCCAACTATGTTAATAGGCTCACCAACTCAGCCCTAAACTCAATAG
Brachyhypopomus_diazi_2408 GCTTAAGATAT-AAGCCAACTACGTTAATAAGCCCCCTAACCCAGCTTTAAACTCAATAG
Brachyhypopomus_diazi_305 GCTTAAGATAT-AAGCCAACTACGTTAATAAGCCCCC-AACCCAGCTTTAAACTCAATAG
Brachyhypopomus_n._sp._PAL_2432 GCTTAAGATAT-AAGCCAACTACGTTAATAAACTTATTAAACAAGTCTTAAACTCAATAG
Electrophorus_electricus_2026 GCTTAAGATTA-AAGTCATCTACATTAATAAGTTAC----ACTTAAACCAAGTA----AA
Electrophorus_electricus_2619 GCTTAAGATTA-AAGTCATCTACATTAATAAGTTAC----ACTTAAACCAAGTA----AA
Gymnotus_aff._anguillaris_2091 GCTTAAGACAC-AAGTCAACTATGTTAATAATTTGTCAC-ACCTAAATTAAACT--ATAA
Gymnotus_arapaima_2002 GCTTAAGACAT-AAGCCAACTATGTTAATAGCCTATT--TAAATAGCCTAAACT--GTAA
Gymnotus_arapaima_2003 GCTTAAGACAT-AAGCCAACTATGTTAATAGCCTATT--TAAATAGCCTAAACT--GTAA
Gymnotus_ardilai_8175 GCTTAAGACAT-AAGCCAACTATGTTAATAACCTATT--TAAATAGGCTAAACT--GTAA
Gymnotus_ardilai_8186 GCTTAAGACAT-AAGCCAACTATGTTAATAACCTATT--TAAATAGGCTAAACT--GTAA
Gymnotus_bahianus_7244 GCTTAAGACAT-AAGCCAACTATGTTAATAGCCTATT--TAAATAGCCTAAACT--GTAA
Gymnotus_bahianus_7245 GCTTAAGACAT-AAGCCAACTATGTTAATAGCCTATT--TAAATAGCCTAAACT--GTAA
Gymnotus_carapo_(CA)_2004 GCTTAAGACAT-AAGCCAACTATGTTAATAGCCTATT--TAAATAGCCTAAACT--GTAA
Gymnotus_carapo_(CA)_2030 GCTTAAGACAT-AAGCCAACTATGTTAATAGCCTATT--TAAATAGCCTAAACT--GTAA
Gymnotus_carapo_(OR)_2040 GCTTAAGACAT-AAGCCAACTATGTTAATAACCTATT--TAAATAGGCTAAACT--GTAA
Gymnotus_carapo_(OR)_2041 GCTTAAGACAT-AAGCCAACTATGTTAATAACCTATT--TAAATAGGCTAAACT--GTAA
Gymnotus_carapo_(WA)_2006 GCTTAAGACAT-AAGCCAACTATGTTAATAGCCTATT--TAAATAGCCTAAACT--GTAA
Gymnotus_carapo_(WA)_2007 GCTTAAGACAT-AAGCCAACTATGTTAATAGCCTATT--TAAATAGCCTAAACT--GTAA
Gymnotus_cataniapo_2062 GCTTAAGACAC-AAACCAACTATGTTAATAATTTACCCC-ACCTAAATTAAACT--GTAA
Gymnotus_cataniapo_2063 GCTTAAGACAC-AAACCAACTATGTTAATAATTTACCCC-ACCTAAATTAAACT--GTAA
Gymnotus_chaviro_7357 GCTTAAGACAT-AAGCCAACTATGTTAATAATCTACC--TATCTAGATTAAACT--GTAA
Gymnotus_chaviro_7358 GCTTAAGACAT-AAGCCAACTATGTTAATAATCTACC--TATCTAGATTAAACT--GTAA
Gymnotus_choco_8209 GCTTAAGACAT-AAGCCAACTATGTTAATAACCTATT--TAAATAGGCTAAACT--GTAA
Gymnotus_coatesi_2042 GCTTAAAACAC-AAGCCACCCACGTCAATAGCCTTAAT-AACCTAGACTAAACA--ACAG
Gymnotus_coatesi_2043 GCTTAAAACAC-AAGCCACCCACGTCAATAGCCTTAAT-AACCTAGACTAAACA--ACAG
Gymnotus_coropinae_(CA)_2010 GCTTAAAACAC-AAGCCACCCACGTCAATGGTCTTAGT-AACCCAGACTAAACA--ACAA
Gymnotus_coropinae_(CA)_2025 GCTTAAAACAC-AAGCCACCCACGTCAATGGTCTTAGT-AACCCAGACTAAACA--ACAA
Gymnotus_coropinae_(GU)_2035 GCTTAAAACAC-AAGCCACCCACGTCAATGGTCTTAGT-AACCCAGACTAAACA--ACAA
Gymnotus_coropinae_(GU)_2036 GCTTAAAACAC-AAGCCACCCACGTCAATGGTCTTAGT-AACCCAGACTAAACA--ACAA
Gymnotus_coropinae_(GU)_2037 GCTTAAAACAC-AAGCCACCCACGTCAATGGTCTTAGT-AACCCAGACTAAACA--ACAA
Gymnotus_coropinae_(GU)_2038 GCTTAAAACAC-AAGCCACCCACGTCAATGGTCTTAGT-AACCCAGACTAAACA--ACAA
Gymnotus_curupira_2009 GCTTAAGACAT-AAGTCAACTATGTTAATAATTTATT--TATCTAAATTAAACT--GTAA
Gymnotus_curupira_2019 GCTTAAGACAT-AAGTCAACTATGTTAATAATTTATT--TATCTAAATTAAACT--GTAA
87
Gymnotus_curupira_2021 GCTTAAGACAT-AAGTCAACTATGTTAATAATTTATT--TATCTAAATTAAACT--GTAA
Gymnotus_curupira_2024 GCTTAAGACAT-AAGTCAACTATGTTAATAATTTATT--TATCTAAATTAAACT--GTAA
Gymnotus_cylindricus_2092 GCTTAAGATAT-AAGCCAACTATGTTAATAGTCTATTCATATATAAACTAAACT--GTAA
Gymnotus_cylindricus_2093 GCTTAAGATAT-AAGCCAACTATGTTAATAGTCTATTCATATATAAACTAAACT--GTAA
Gymnotus_cylindricus_2094 GCTTAAGATAT-AAGCCAACTATGTTAATAGTCTATTCATATATAAACTAAACT--GTAA
Gymnotus_henni_7276 GCTTAAGACAC-AAGCCAACTATGTTAATAGCCTTCA--CACCCAGACTAAACT--GTAA
Gymnotus_henni_7277 GCTTAAGACAC-AAGCCAACTATGTTAATAGCCTTCA--CACCCAGACTAAACT--GTAA
Gymnotus_henni_8189 GCTTAAGACAC-AAGCCAACTATGTTAATAGCCTTCA--CACCCAGACTAAACT--GTAA
Gymnotus_henni_8193 GCTTAAGACAC-AAGCCAACTATGTTAATAGCCTTCA--CACCCAGACTAAACT--GTAA
Gymnotus_henni_8207 GCTTAAGACAC-AAGCCAACTATGTTAATAGCCTTTA--CACCCAGACTAAACT--GTAA
Gymnotus_henni_8230 GCTTAAGACAC-AAGCCAACTATGTTAATAGCCTTCA--CACCCAGACTAAACT--GTAA
Gymnotus_henni_8231 GCTTAAGACAC-AAGCCAACTATGTTAATAGCCTTCA--CACCCAGACTAAACT--GTAA
Gymnotus_javari_2020 GCTTAAAACAC-AAGCCACCCACGTCAATAGCCTTAAT-AACCTAGACTAAACA--ACAG
Gymnotus_jonasi_2016 GCTTAAGACAT--AGCCACCCGCGTTAATAGCTTGTAT-AACTCAGACTAAACA--ACAA
Gymnotus_jonasi_2471 GCTTAAGACAT--AGCCACCCGCGTTAATAGCTTGTAT-AACTCAGGCTAAACA--ACAA
Gymnotus_maculosus_8126 GCTTAAGATAT-AAGCCAACTATGTTAATAGTCTATTCATATATAAACTAAACT--GTAA
Gymnotus_maculosus_8137 GCTTAAGATAT-AAGCCAACTATGTTAATAGTCTATTCATATATAAACTAAACT--GTAA
Gymnotus_maculosus_8169 GCTTAAGATAT-AAGCCAACTATGTTAATAGTCTATTCATATATAAACTAAACT--GTAA
Gymnotus_maculosus_8213 GCTTAAGATAT-AAGCCAACTATGTTAATAGTCTATTCATATATAAACTAAACT--GTAA
Gymnotus_mamiraua_2012 GCTTAAGACAC-AAGCCAACTATGTTAATAACCTATT--TAAGTAGACTAAACT--GTAA
Gymnotus_mamiraua_2013 GCTTAAGACAC-AAGCCAACTATGTTAATAACCTATT--TAAGTAGACTAAACT--GTAA
Gymnotus_n._sp._7104 GCTTAAGATAT-AAGCCAACTATGTTAATAATTTATT--TATCTAAATTAAACT--GTAA
Gymnotus_n._sp._7105 GCTTAAGATAT-AAGCCAACTATGTTAATAATTTATT--TATCTAAATTAAACT--GTAA
Gymnotus_n._sp._CORU_2558 GCTTAAGACAT-AAGCCAACTATGTTAATAGCCTATT--TAAATAGGCTAAACT--GTAA
Gymnotus_n._sp._FRIT_7109 GCTTAAGACAC-AAGCCAACTATGTTAATAATTTACCTCGACCTAAATTAAACT--GTAA
Gymnotus_n._sp._ITAP_2559 GCTTAAGACAC-AAGCCAACTATGTTAATAACCTATT--TAAGTAGGCTAAACT--GTAA
Gymnotus_n._sp._ITAP_7071 GCTTAAGACAC-AAGCCAACTATGTTAATAACCTATT--TAAGTAGGCTAAACT--GTAA
Gymnotus_n._sp._ITAP_7072 GCTTAAGACAC-AAGCCAACTATGTTAATAACCTATT--TAAGTAGGCTAAACT--GTAA
Gymnotus_n._sp._ITAP_7074 GCTTAAGACAC-AAGCCAACTATGTTAATAACCTATT--TAAGTAGGCTAAACT--GTAA
Gymnotus_n._sp._ITAP_7075 GCTTAAGACAC-AAGCCAACTATGTTAATAACCTATT--TAAGTAGGCTAAACT--GTAA
Gymnotus_n._sp._MAMA_7065 GCTTAAGACAT-AAGCCAACTATGTTAATAGCCTATT--TAAATAGGCTAAACT--GTAA
Gymnotus_n._sp._MAMA_7066 GCTTAAGACAT-AAGCCAACTATGTTAATAGCCTATT--TAAATAGGCTAAACT--GTAA
Gymnotus_n._sp._MAMA_7067 GCTTAAGACAT-AAGCCAACTATGTTAATAGCCTATT--TAAATAGGCTAAACT--GTAA
Gymnotus_n._sp._RS1_7088 GCTTAAGACAT-AAGCCAACTATGTTAATAGCCTATT--TAAATAGGCTAAACT--GTAA
Gymnotus_n._sp._XING_7305 GCTTAAGACAT-AAGCCAACTATGTTAATAATTTATT--TATCTAAATTAAACT--GTAA
Gymnotus_obscurus_2017 GCTTAAGACAT-AAGCCAACTATGTTAATAATTTACC--TACCTAAATTAAACT--GTAA
Gymnotus_obscurus_2018 GCTTAAGACAT-AAGCCAACTATGTTAATAATTTACC--TACCTAAATTAAACT--GTAA
Gymnotus_omarorum_7092 GCTTAAGACAT-AAGCCAACTATGTTAATAGCCTGTT--TAAATAGGCTAAACT--GTAA
Gymnotus_omarorum_7093 GCTTAAGACAT-AAGCCAACTATGTTAATAGCCTGTT--TAAATAGG-TAAACT--GTAA
Gymnotus_panamensis_8018 GCTTAAGACATTAAGCCAACTATGTTAATAATTTATACATACATAAACTAAACT--GTAA
Gymnotus_panamensis_8021 GCTTAAGACATTAAGCCAACTATGTTAATAATTTATACATACATAAACTAAACT--GTAA
Gymnotus_panamensis_8210 GCTTAAGACATTAAGCCAACTATGTTAATAATTTATACATACATAAACTAAACT--GTAA
Gymnotus_pantanal_7076 GCTTAAGATAT-AAGCCAACTATGTTAATAATTTATT--TATCTAAATTAAACT--GTAA
Gymnotus_pantherinus_2039 GCTTAAGACAC-AAGCCAATTATGTTAATAGCCTAAA--CACCTAGACTAAACT--ATAC
Gymnotus_pantherinus_2945 GCTTAAGACAC-AAGCCAATTATGTTAATAGCCTAAA--TACCTAGACTAAACT--ATAC
Gymnotus_pantherinus_7111 GCTTAAGACAC-AAGCCAATTATGTTAATAGCCTAAA--TACCTAGACTAAACT--ATAC
Gymnotus_pedanopterus_2058 GCTTAAGACAC-AAGCCAACCATGTCAATAATTTACA--CACCTAAATTAAACT--ATAA
Gymnotus_pedanopterus_2059 GCTTAAGACAC-AAGCCAACCATGTCAATAATTTACA--CACCTAAATTAAACT--ATAA
Gymnotus_stenoleucus_2060 GCTTAAAACAC-AAGCCACCCACGTCAATGGTCTTAAT-AACCCAGACTAAACA--ACAA
Gymnotus_stenoleucus_2061 GCTTAAAACAC-AAGCCACCCACGTCAATGGTCTTAAT-AACCCAGACTAAACA--ACAA
Gymnotus_stenoleucus_2064 GCTTAAAACAC-AAGCCACCCACGTCAATGGTCTTAAT-AACCCAGACTAAACA--ACAA
Gymnotus_sylvius_7239 GCTTAAGACAT-AAGCCAACTATGTTAATAGCCTATT--TAAATAGGCTAAACT--GTAA
Gymnotus_sylvius_7240 GCTTAAGACAT-AAGCCAACTATGTTAATAGCCTATT--TAAATAGGCTAAACT--GTAA
Gymnotus_tigre_7090 GCTTAAGACAT-AAGCCAACTATGTTAATAGCCTACA--CACCTAGACTAAACT--GCAA
Gymnotus_tigre_7349 GCTTAAGACAT-AAGCCAACTATGTTAATAGCCTACA--CACCTAGACTAAACT--GCAA
Gymnotus_ucamara_1927 GCTTAAGACAT-AAGCCAACTATGTTAATAGCCTATT--TAAATAGCCTAAACT--GTAA
Gymnotus_ucamara_1950 GCTTAAGACAT-AAGCCAACTATGTTAATAGCCTATT--TAAATAGCCTAAACT--GTAA
Gymnotus_varzea_2014 GCTTAAGACAT-AAGCCAACTATGTTAATAATCTACC--TATCTAGATTAAACT--GTAA
Gymnotus_varzea_2015 GCTTAAGACAT-AAGCCAACTATGTTAATAATCTACC--TATCTAGATTAAACT--GTAA
Hypopomus_artedi_2232 GCTTAAGACAT-CAACCAACTATATTAATAGGCTCACCAACCGAGACTTAAACTCAATAG
Rhamphichthys_rostratus_2632 GCTTAAGACAC-AAGCCAACTATGTTAATAAACCATA-TAACCTGGCTTAAACTAAATAG
Sternopygus_astrabes_2203 GCTTAAGACCT-AAGCCACCTATGTTAATAGTACAAA-TAAACCAAACTAAACTAAATAG
Sternopygus_macrurus_2639 GCTTAAGACCT-AAACCACCTATGTTAATAATCTA---CAAACTAGTTTAAACTAAATAG
Brachyhypopomus_brevirostris_2617 TC-ATGGCCCAC---ATCTTCGGTTGGGGCGACAATGGAGAAAAACAAAGCCTCCACGCG
Brachyhypopomus_diazi_2408 TT-ATGGCCCAC---ATCTTCGGTTGGGGCGACAATGGAGGAAAACAAAGCCTCCACGCG
Brachyhypopomus_diazi_305 TT-ATGGCCCAC---ATCTTCGGTTGGGGCGACAATGGAGGAAAACAAAGCCTCCACGCG
Brachyhypopomus_n._sp._PAL_2432 CT-GTGGCCCGT---ATCTTCGGTTGGGGCGACAATGGAGGAAAACAAAGCCTCCACGTG
Electrophorus_electricus_2026 TA-CTGACCTAC---ATCTTCGGTTGGGGCGACCACGGGGGAAAACTAAGCCCCCATGAA
Electrophorus_electricus_2619 TA-CTGACCTAC---ATCTTCGGTTGGGGCGACCACGGGGGAAAACTAAGCCCCCATGAA
Gymnotus_aff._anguillaris_2091 CA-CTGACCCCCCCCGTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCATGCG
Gymnotus_arapaima_2002 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCACGCG
Gymnotus_arapaima_2003 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACGAAACCTCCACGCG
88
Gymnotus_ardilai_8175 CA-CTGGCCCCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCACGAG
Gymnotus_ardilai_8186 CA-CTGGCCCCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCACGAG
Gymnotus_bahianus_7244 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCACGCG
Gymnotus_bahianus_7245 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCACGCG
Gymnotus_carapo_(CA)_2004 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCACGCG
Gymnotus_carapo_(CA)_2030 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCACGCG
Gymnotus_carapo_(OR)_2040 CA-CTGGCCCCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCACGAG
Gymnotus_carapo_(OR)_2041 CA-CTGGCCCCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCACGAG
Gymnotus_carapo_(WA)_2006 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCACGCG
Gymnotus_carapo_(WA)_2007 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCACGCG
Gymnotus_cataniapo_2062 CA-CTGGCCATA---GTCTTCGGTTGGGGCGACCACGGAGTAAAATAAAACCTCCATGCG
Gymnotus_cataniapo_2063 CA-CTGGCCATA---GTCTTCGGTTGGGGCGACCACGGAGTAAAATAAAACCTCCATGCG
Gymnotus_chaviro_7357 CA-CTGGCCTAA---ATCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCATGTA
Gymnotus_chaviro_7358 CA-CTGGCCTAA---ATCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCATGTA
Gymnotus_choco_8209 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACGAAACCTCCACGAG
Gymnotus_coatesi_2042 CA-CTGGCC-CA---GTTTTCGGTTGGGGCGACCACGGAGTAAAATAAAACCCCCATGCA
Gymnotus_coatesi_2043 CA-CTGGCC-CA---GTTTTCGGTTGGGGCGACCACGGAGTAAAATAAAACCCCCATGCA
Gymnotus_coropinae_(CA)_2010 CA-TTGGCC-CA---GTTTTCGGTTGGGGCGACCACGGAGTAAAATAAAACCCCCATGCA
Gymnotus_coropinae_(CA)_2025 CA-TTGGCC-CA---GTTTTCGGTTGGGGCGACCACGGAGTAAAATAAAACCCCCATGCA
Gymnotus_coropinae_(GU)_2035 CA-TTGGCC-CA---GTTTTCGGTTGGGGCGACCACGGAGTAAAATAAAACCCCCATGCA
Gymnotus_coropinae_(GU)_2036 CA-TTGGCC-CA---GTTTTCGGTTGGGGCGACCACGGAGTAAAATAAAACCCCCATGCA
Gymnotus_coropinae_(GU)_2037 CA-TTGGCC-CA---GTTTTCGGTTGGGGCGACCACGGAGTAAAATAAAACCCCCATGCA
Gymnotus_coropinae_(GU)_2038 CA-TTGGCC-CA---GTTTTCGGTTGGGGCGACCACGGAGTAAAATAAAACCCCCATGCA
Gymnotus_curupira_2009 CA-CTGACCTAA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCATGAG
Gymnotus_curupira_2019 CA-CTGACCTAA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCATGAG
Gymnotus_curupira_2021 CA-CTGACCTAA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCATGAG
Gymnotus_curupira_2024 CA-CTGACCTAA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCATGAG
Gymnotus_cylindricus_2092 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAATAAAACCTCCATGCG
Gymnotus_cylindricus_2093 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAATAAAACCTCCATGAG
Gymnotus_cylindricus_2094 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAATAAAACCTCCATGAG
Gymnotus_henni_7276 CATCTGGCCCTA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACGAAACCTCCACGCG
Gymnotus_henni_7277 CATCTGGCCCTA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACGAAACCTCCACGCG
Gymnotus_henni_8189 CATCTGGCCCTA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACGAAACCTCCACGCG
Gymnotus_henni_8193 CATCTGGCCCTA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACGAAACCTCCACGCG
Gymnotus_henni_8207 CATCTGGCCCCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACGAAACCTCCACGCG
Gymnotus_henni_8230 CATCTGGCCCTA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACGAAACCTCCACGCG
Gymnotus_henni_8231 CATCTGGCCCTA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACGAAACCTCCACGCG
Gymnotus_javari_2020 CA-CTGGCC-CA---GTTTTCGGTTGGGGCGACCACGGAGTAAAATAAAACCCCCATGCA
Gymnotus_jonasi_2016 TA-CTGGC-TCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAATGAAACCTCCATGCA
Gymnotus_jonasi_2471 TA-CTGGC-TCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAATGAAACCTCCATGCA
Gymnotus_maculosus_8126 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAATAAAACCTCCATGCG
Gymnotus_maculosus_8137 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAATAAAACCTCCATGCG
Gymnotus_maculosus_8169 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAATAAAACCTCCATGCG
Gymnotus_maculosus_8213 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAATAAAACCTCCATGCG
Gymnotus_mamiraua_2012 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAGAACAAAGCCTCCACGCG
Gymnotus_mamiraua_2013 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAGAACAAAGCCTCCACGCG
Gymnotus_n._sp._7104 CA-CTGGTCTAA---ATCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCATGCG
Gymnotus_n._sp._7105 CA-CTGGTCTAA---ATCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCATGCG
Gymnotus_n._sp._CORU_2558 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCACGCG
Gymnotus_n._sp._FRIT_7109 CA-CTGGCCGCC---GTCTTCGGTTGGGGCGACCATGGAGTAAAACAAAACCTCCCTGCG
Gymnotus_n._sp._ITAP_2559 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCACGCG
Gymnotus_n._sp._ITAP_7071 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAGAACAAAACCTCCACGCG
Gymnotus_n._sp._ITAP_7072 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAGAACAAAACCTCCACGCG
Gymnotus_n._sp._ITAP_7074 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAGAACAAAACCTCCACGCG
Gymnotus_n._sp._ITAP_7075 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCACGCG
Gymnotus_n._sp._MAMA_7065 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCACGCG
Gymnotus_n._sp._MAMA_7066 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCACGCG
Gymnotus_n._sp._MAMA_7067 CA-CTGG-CTCA---GTCTTCGG-TGGGGCGACCACGGAGTAAAACAAAACCTCCACGCG
Gymnotus_n._sp._RS1_7088 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCACGCG
Gymnotus_n._sp._XING_7305 CA-CTGGCCTAA---ATCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCATGCG
Gymnotus_obscurus_2017 CA-CTGGCCTAA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCATGCG
Gymnotus_obscurus_2018 CA-CTGGCCTAA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCATGCG
Gymnotus_omarorum_7092 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACGAAACCTCCACGCG
Gymnotus_omarorum_7093 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACGAAACCTCCACGCG
Gymnotus_panamensis_8018 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACGAAACCTCCATGCG
Gymnotus_panamensis_8021 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACGAAACCTCCATGCG
Gymnotus_panamensis_8210 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACGAAACCTCCATGCG
Gymnotus_pantanal_7076 CA-CTGGTCTAA---ATCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCATGCG
Gymnotus_pantherinus_2039 CA-CTGGCCCCA---GTCTTCGGTTGGGGCGACCACGGAGCAAAACAAAACCTCCATGAG
Gymnotus_pantherinus_2945 CA-CTGGCCCCA---GTCTTCGGTTGGGGCGACCACGGAGCAAAATAAAACCTCCATGAG
Gymnotus_pantherinus_7111 CA-CTGGCCCCA---GTCTTCGGTTGGGGCGACCACGGAGCAAAATAAAACCTCCATGAG
Gymnotus_pedanopterus_2058 CA-CTGGCCCTC---GTCTTCGGTTGGGGCGACCACGGAGTAAAATAAAACCTCCATGCG
Gymnotus_pedanopterus_2059 CA-CTGGCCCTC---GTCTTCGGTTGGGGCGACCACGGAGTAAAATAAAACCTCCATGCG
89
Gymnotus_stenoleucus_2060 CA-CTGGCC-CA---GTTTTCGGTTGGGGCGACCACGGAGTAAAATAAAACCCCCATGCA
Gymnotus_stenoleucus_2061 CC-CTGGCC-CA---GTTTTCGGTTGGGGCGACCACGGAGTAAAATAAAACCCCCATGCA
Gymnotus_stenoleucus_2064 CA-CTGGCC-CA---GTTTTCGGTTGGGGCGACCACGGAGTAAAATAAAACCCCCATGCA
Gymnotus_sylvius_7239 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCACGCG
Gymnotus_sylvius_7240 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCACGCG
Gymnotus_tigre_7090 CA-CTGGCCCTA---GTCTTCGGTTGGGGCGACCACGGAGCAAAACAAAACCTCCATGCG
Gymnotus_tigre_7349 CA-CTGGCCCTA---GTCTTCGGTTGGGGCGACCACGGAGCAAAACAAAACCTCCATGCG
Gymnotus_ucamara_1927 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCACGCG
Gymnotus_ucamara_1950 CA-CTGGCCTCA---GTCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCACGCG
Gymnotus_varzea_2014 CA-CTGGCCTAA---ATCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCATGTA
Gymnotus_varzea_2015 CA-CTGGCCTAA---ATCTTCGGTTGGGGCGACCACGGAGTAAAACAAAACCTCCATGTA
Hypopomus_artedi_2232 AC-CTGGCCCCCC--GTCTTCAGTTGGGGCGACGATGGAGAAAAATAAAGCCTCCACGCA
Rhamphichthys_rostratus_2632 AA-CTGGCCCCC---GTCTTCGGTTGGGGCGACCGCGGGGGAAAACAAAGCCCCCACGTG
Sternopygus_astrabes_2203 TC-CTGACCCAA---GTCTTCGGTTGGGGTGACCGCGGGGGAAAACAAAGCCCCCACGTG
Sternopygus_macrurus_2639 CA-TTGGCCCAA---GTCTTCGGTTGGGGTGACCGCGGGGGAAAACAAAGCCCCCATGTG
Brachyhypopomus_brevirostris_2617 GCACGGGACTTC--CCCAAAAATCAAGAGCAACCCCTCTAAATCTCAGAACCTCTGACCA
Brachyhypopomus_diazi_2408 GTATGGGATACC--CCCAAAAATCAAGAGCAACCCCTCTAAATCTCAGAACCTCTGACCT
Brachyhypopomus_diazi_305 GTATGGGGTACC--CCCAAAAATCAAGAGCAACCCCTCTAAATCTCAGAACCTCTGACCT
Brachyhypopomus_n._sp._PAL_2432 GTATGGGACTAC--CCCAAAAATCAAGAGCAACCCCTCTAAATCTCAGAACCTCTGACCT
Electrophorus_electricus_2026 GAAAGATAGACC--CTTCTAAACCTAGAAAGACATTTCTAAGTCGCAGAACATCTGACTA
Electrophorus_electricus_2619 GAAAGATAGACC--CTTCTAAACCTAGAAAGACATTTCTAAGTCGCAGAACATCTGACTA
Gymnotus_aff._anguillaris_2091 GATAGGGCACA---CCCTAAAACCAAGAGAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_arapaima_2002 GATAGGGAATA---CCCTAAAACCAAGAGAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_arapaima_2003 GATAGGGAATA---CCCTAAAACCAAGAGAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_ardilai_8175 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAATATCTGACCA
Gymnotus_ardilai_8186 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAATATCTGACCA
Gymnotus_bahianus_7244 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_bahianus_7245 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_carapo_(CA)_2004 GATAGGGAATA---CCCTAAAACCAAGAGAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_carapo_(CA)_2030 GATAGGGAATA---CCCTAAAACCAAGAGAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_carapo_(OR)_2040 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAATATCTGACCA
Gymnotus_carapo_(OR)_2041 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAATATCTGACCA
Gymnotus_carapo_(WA)_2006 GATAGGGAATA---CCCTAAAACCAAGAGAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_carapo_(WA)_2007 GATAGGGAATA---CCCTAAAACCAAGAGAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_cataniapo_2062 GATAGGGCATA---CCCTAAAACCAAGAAAGACACTTCCAAGCCCCAGAACATCTGACCT
Gymnotus_cataniapo_2063 GATAGGGCATA---CCCTAAAACCAAGAAAGACACTTCCAAGCCACAGAACATCTGACCT
Gymnotus_chaviro_7357 GATAGGGAATA---TCCTAAAACCAAGAGAAACATCTCCAAGTCACAGAATATCTGACTA
Gymnotus_chaviro_7358 GATAGGGAATA---TCCTAAAACCAAGAGAAACATCTCCAAGTCACAGAATATCTGACTA
Gymnotus_choco_8209 GATAGGGAATA---TCCTAAAACCAAGAGAAACATCTCCAAGTCACAGAATATCTGACCA
Gymnotus_coatesi_2042 GACAGGGAATA---CCCTAAAACCAAGAAAAACATTTCTAAGTCACAGAACATCTGACTA
Gymnotus_coatesi_2043 GACAGGGAATA---CCCTAAAACCAAGAAAAACATTTCTAAGTCACAGAACATCTGACTA
Gymnotus_coropinae_(CA)_2010 GACAGGGAATA---CCCTAAAACCAAGAAAAACATTTCTAAGTCACAGAACATCTGACTA
Gymnotus_coropinae_(CA)_2025 GACAGGGAATA---CCCTAAAACCAAGAAAAACATTTCTAAGTCACAGAACATCTGACTA
Gymnotus_coropinae_(GU)_2035 GACAGGGAATA---CCCTAAAACCAAGAAAAACATTTCTAAGTCACAGAACATCTGACTA
Gymnotus_coropinae_(GU)_2036 GACAGGGAATA---CCCTAAAACCAAGAAAAACATTTCTAAGTCACAGAACATCTGACTA
Gymnotus_coropinae_(GU)_2037 GACAGGGAATA---CCCTAAAACCAAGAAAAACATTTCTAAGTCACAGAACATCTGACT-
Gymnotus_coropinae_(GU)_2038 GACAGGGAATA---CCCTAAAACCAAGAAAAACATTTCTAAGTCACAGAACATCTGACT-
Gymnotus_curupira_2009 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAACATCTGACCA
Gymnotus_curupira_2019 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAACATCTGACCA
Gymnotus_curupira_2021 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAACATCTGACCA
Gymnotus_curupira_2024 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAACATCTGACCA
Gymnotus_cylindricus_2092 GATAGGGAAAAA--TCCTAAAATCAAGAGAGACATCTCCAAATCACAGAATATCTGACCA
Gymnotus_cylindricus_2093 GATAGGGAAAAA--TCCTAAAATCGAGAGAGACATCTCCAAATCACAGAATATCTGACCA
Gymnotus_cylindricus_2094 GATAGGGAAAAA--CCCTAAAATCGAGAGAGACATCTCCAAATCACAGAATATCTGACCA
Gymnotus_henni_7276 GATAAGGATATA--TCCTAAAACTAAGAAAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_henni_7277 GATAAGGATATA--TCCTAAAACTAAGAAAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_henni_8189 GATAAGGATATA--TCCTAAAACTAAGAAAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_henni_8193 GATAAGGATATA--TCCTAAAACTAAGAAAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_henni_8207 GATAGGAATATA--TCCTAAAACTAAGAGAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_henni_8230 GATAAGGATATA--TCCTAAAACTAAGAGAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_henni_8231 GATAAGGATATA--TCCTAAAACTAAGAGAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_javari_2020 GACAGGGAATA---CCCTAAAACCAAGAAAAACATTTCTAAGTCACAGAACATCTGACTA
Gymnotus_jonasi_2016 GACAGGGAATA---CCCTAAAACCAAGAAAGACATTTCTAAGTCACAGAACATCTGACTA
Gymnotus_jonasi_2471 GACAGGGAATA---CCCTAAAACCAAGAAAGACATTTCTAAGTCACAGAACATCTGACTA
Gymnotus_maculosus_8126 GATAGGGAAAAA--TCCTAAAATCAAGAGAGACATCTCCAAATCACAGAATATCTGACCA
Gymnotus_maculosus_8137 GATAGGGAAAAA--TCCTAAAATCAAGAGAGACATCTCCAAATCACAGAATATCTGACCA
Gymnotus_maculosus_8169 GATAGGGAAAAA--TCCTAAAATCAAGAGAGACATCTCCAAATCACAGAATATCTGACCA
Gymnotus_maculosus_8213 GATAGGGAAAAA--TCCTAAAATCAAGAGAGACATCTCCAAATCACAGAATATCTGACCA
Gymnotus_mamiraua_2012 GATAGGGAATA---CCCTAAAACCAAGAGAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_mamiraua_2013 GATAGGGAATA---CCCTAAAACCAAGAGAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_n._sp._7104 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAATATCTGACCA
Gymnotus_n._sp._7105 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAATATCTGACCA
90
Gymnotus_n._sp._CORU_2558 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAACATCTGACCA
Gymnotus_n._sp._FRIT_7109 GATAGGACATA---CCCTAAAACCAAGAAAGACACTTCTAAGCCACAGAACATCTGACCT
Gymnotus_n._sp._ITAP_2559 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_n._sp._ITAP_7071 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_n._sp._ITAP_7072 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_n._sp._ITAP_7074 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_n._sp._ITAP_7075 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_n._sp._MAMA_7065 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAACATCTGACCA
Gymnotus_n._sp._MAMA_7066 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAACATCTGACCA
Gymnotus_n._sp._MAMA_7067 GATAGGGAATA---TCCTAAAACCAAGA-AGACATCTCCAAGTCACAGAACATCTGACCA
Gymnotus_n._sp._RS1_7088 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAACATCTGACCA
Gymnotus_n._sp._XING_7305 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAATATCTGACCA
Gymnotus_obscurus_2017 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAATATCTGACCA
Gymnotus_obscurus_2018 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAATATCTGACCA
Gymnotus_omarorum_7092 GATAGGGAATA---CCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAACATCTGACCA
Gymnotus_omarorum_7093 GATAGGGAATA---CCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAACATCTGACCA
Gymnotus_panamensis_8018 GATAGGGAAAAA--TCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAATATCTGACCA
Gymnotus_panamensis_8021 GATAGGGAAAAA--TCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAATATCTGACCA
Gymnotus_panamensis_8210 GATAGGGAAAAA--TCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAATATCTGACCA
Gymnotus_pantanal_7076 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAATATCTGACCA
Gymnotus_pantherinus_2039 GATAGGGAATA---CCCTAAAACCAAGAGAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_pantherinus_2945 GATAGGGAATA---CCCTAAAACCAAGAGAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_pantherinus_7111 GATAGGGAATA---CCCTAAAACCAAGAGAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_pedanopterus_2058 GATTAGGACACA--TCCTAAAACCAAGAGAGACACCTCCAAGCCACAGAACATCTGACCA
Gymnotus_pedanopterus_2059 GATTAGGACACA--TCCTAAAACCAAGAGAGACACCTCCAAGCCACAGAACATCTGACCA
Gymnotus_stenoleucus_2060 GACAGGGAATA---CCCTAAAACCAAGAAAAACATTTCTAAGTCACAGAACATCTGACTA
Gymnotus_stenoleucus_2061 GACAGGGAATA---CCCTAAAACCAAGAAAAACATTTCTAAGTCACAGAACATCTGACTA
Gymnotus_stenoleucus_2064 GACAGGGAATA---CCCTAAAACCAAGAAAAACATTTCTAAGTCACAGAACATCTGACTA
Gymnotus_sylvius_7239 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAACATCTGACCA
Gymnotus_sylvius_7240 GATAGGGAATA---TCCTAAAACCAAGAGAGACATCTCCAAGTCACAGAACATCTGACCA
Gymnotus_tigre_7090 GATAGGGAATA---CCCTAAAACTAAGAGATACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_tigre_7349 GATAGGGAATA---CCCTAAAACTAAGAGATACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_ucamara_1927 GATAGGGAATA---CCCTAAAACCAAGAGAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_ucamara_1950 GATAGGGAATA---CCCTAAAACCAAGAGAGACATCTCCAAGCCACAGAACATCTGACCA
Gymnotus_varzea_2014 GATAGGGAATA---TCCTAAAACCAAGAGAAACATCTCCAAGTCACAGAATATCTGACTA
Gymnotus_varzea_2015 GATAGGGAATA---TCCTAAAACCAAGAGAAACATCTCCAAGTCACAGAATATCTGACTA
Hypopomus_artedi_2232 GCATGGAATTTT--CCTAAAA-TCAAGAGTAACCCCTCAAAACCTCAGAATCTCTGACCT
Rhamphichthys_rostratus_2632 GAGTGAGGATATTACCTTACAACCAAGAGAGACCCCTCTAAGTCACAGAACTTCTGACCA
Sternopygus_astrabes_2203 GAATGGGGCCAACCCCC-AAAACCATGAGAGACATCTCTAAGTCGCAGAACATCTGACCA
Sternopygus_macrurus_2639 GAACGGGGACAGCCCCCTAAAACCAAGAGAGACATCTCTAAGCCCCAGAACATCTGACCA
Brachyhypopomus_brevirostris_2617 AATA-GATCCGGCTCCT--CGCCGATCAACGGACCAAGTTACCCTAGGGATAACAGCGCA
Brachyhypopomus_diazi_2408 AACA-GATCCGGCTCCT--CGCCGATCAACGGACCAAGTTACCCTAGGGATAACAGCGCA
Brachyhypopomus_diazi_305 AACA-GATCCGGCTCCT--CGCCGATCAACGGACCAAGTTACCCTAGGGATAACAGCGCA
Brachyhypopomus_n._sp._PAL_2432 AATA-GATCCGGCCCCC--CGCCGATCAACGAACCAAGTTACCCTAGGGATAACAGCGCA
Electrophorus_electricus_2026 AAA--GATCCGTTTTTA---TACGACCAGCGAACCAAGTTACCCAAGGGATAACAGCGCA
Electrophorus_electricus_2619 AAA--GATCCGTTTTTA---TACGACCAGCGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_aff._anguillaris_2091 CATA-GATCCGGCCTTC-CAGCCGATCAACGAACCAAGTTACCCTAGGGATAACAGCGCA
Gymnotus_arapaima_2002 CATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_arapaima_2003 CATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_ardilai_8175 AATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_ardilai_8186 AATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_bahianus_7244 CATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_bahianus_7245 CATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_carapo_(CA)_2004 CATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_carapo_(CA)_2030 CATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_carapo_(OR)_2040 AATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_carapo_(OR)_2041 AATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_carapo_(WA)_2006 CATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_carapo_(WA)_2007 CATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_cataniapo_2062 TATACGATCCGGCCTTT-AGGCCGATCAGCGGACCAAGTTACCCTAGGGATAACAGCGCA
Gymnotus_cataniapo_2063 TATACGATCCGGCCTTT-AGGCCGATCAGCGGACCAAGTTACCCTAGGGATAACAGCGC-
Gymnotus_chaviro_7357 TATA-GATCCGGCCCTT-CAGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_chaviro_7358 TATA-GATCCGGCCCTT-CAGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_choco_8209 AATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_coatesi_2042 TATA-GATCCGGCCTTC-CGGCCGATCAACGAACCAAGTTACCCCAGGGATAACAGCGCA
Gymnotus_coatesi_2043 TATA-GATCCGGCCTTC-CGGCCGATCAACGAACCAAGTTACCCCAGGGATAACAGCGCA
Gymnotus_coropinae_(CA)_2010 TACA-GATCCGGCCCTC-CGGCCGATCAACGAACCAAGTTACCCTAGGGATAACAGCGCA
Gymnotus_coropinae_(CA)_2025 TACA-GATCCGGCCCTC-CGGCCGATCAACGAACCAAGTTACCCTAGGGATAACAGCGCA
Gymnotus_coropinae_(GU)_2035 TACA-GATCCGGCCCTC-CGGCCGATCAACGAACCAAGTTACCCTAGGGATAACAGCGCA
Gymnotus_coropinae_(GU)_2036 TACA-GATCCGGCCCTC-CGGCCGATCAGCGAACCAAGTTACCCTAGGGATAACAGCGCA
Gymnotus_coropinae_(GU)_2037 -ACA-GATCCGGCCCTC-CGGCCGATCAACGAACCAAGTTACCCTAGGGATAACAGCGCA
Gymnotus_coropinae_(GU)_2038 -ACA-GATCCGGCCCTC-CGGCCGATCAACGAACCAAGTTACCCTAGGGATAACAGCGCA
91
Gymnotus_curupira_2009 TATA-GATCCGGCCCTC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_curupira_2019 TATA-GATCCGGCCCTC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_curupira_2021 TATA-GATCCGGCCCTC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_curupira_2024 TATA-GATCCGGCCCTC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_cylindricus_2092 TATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_cylindricus_2093 TATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_cylindricus_2094 TATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_henni_7276 CAT--GATCCGGCCCCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_henni_7277 CAT--GATCCGGCCCCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_henni_8189 CAT--GATCCGGCCCCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_henni_8193 CAT--GATCCGGCCCCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_henni_8207 CAT--GATCCGGCCCCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_henni_8230 CAT--GATCCGGCCCCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_henni_8231 CAT--GATCCGGCCCCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_javari_2020 TATA-GATCCGGCCTTC-CGGCCGATCAACGAACCAAGTTACCCTAGGGATAACAGCGCA
Gymnotus_jonasi_2016 CACA-GATCCGGCCTCT-TGGCCGATCAACGAACCAAGTTACCCCAGGGATAACAGCGCA
Gymnotus_jonasi_2471 CACA-GATCCGGCCTCT-TGGCCGATCAACGAACCAAGTTACCCTAGGGATAACAGCGCA
Gymnotus_maculosus_8126 TATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_maculosus_8137 TATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_maculosus_8169 TATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_maculosus_8213 TATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_mamiraua_2012 TATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_mamiraua_2013 TATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_n._sp._7104 TATA-GATCCGGCCCTC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_n._sp._7105 TATA-GATCCGGCCCTC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_n._sp._CORU_2558 AATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_n._sp._FRIT_7109 CACATGACCCGGCCTTTTAGGCCGATCAACGGACCAAGTTACCCTAGGGATAACAGCGCA
Gymnotus_n._sp._ITAP_2559 TATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_n._sp._ITAP_7071 TATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_n._sp._ITAP_7072 TATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_n._sp._ITAP_7074 TATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_n._sp._ITAP_7075 TATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_n._sp._MAMA_7065 AATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_n._sp._MAMA_7066 AATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_n._sp._MAMA_7067 AATA-GATCCGGCCTCC-CGG-C-AT-AACGAACCAAGTT-CCCAAGGGATAACAGCGCA
Gymnotus_n._sp._RS1_7088 AATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_n._sp._XING_7305 TATA-GATCCGGCCCTC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_obscurus_2017 TATA-GATCCGGCCCTC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_obscurus_2018 TATA-GATCCGGCCCTC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_omarorum_7092 AATA-GATCCGGCCTCC-CGGCCGATCAACGGACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_omarorum_7093 AATA-GATCCGGCCTCC-CGGCCGATCAACGGACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_panamensis_8018 TATA-GATCCGGCCTTC-GGACCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_panamensis_8021 TATA-GATCCGGCCTTC-GGACCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_panamensis_8210 TATA-GATCCGGCCTTC-GGACCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_pantanal_7076 TATA-GATCCGGCCCTC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_pantherinus_2039 TAT--GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCTAGGGATAACAGCGCA
Gymnotus_pantherinus_2945 TAT--GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCTAGGGATAACAGCGCA
Gymnotus_pantherinus_7111 TAT--GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCTAGGGATAACAGCGCA
Gymnotus_pedanopterus_2058 CATA-GATCCGGCCTTT-CAGCCGATCAACGAACCAAGTTACCCTAGGGATAACAGCGCA
Gymnotus_pedanopterus_2059 CATA-GATCCGGCCTTT-CAGCCGATCAACGAACCAAGTTACCCTAGGGATAACAGCGCA
Gymnotus_stenoleucus_2060 TACA-GATCCGGCCCTC-CGGCCGATCAACGAACCAAGTTACCCTAGGGATAACAGCGCA
Gymnotus_stenoleucus_2061 TATA-GATCCGGCCCTC-CGGCCGATCAACGAACCAAGTTACCCTAGGGATAACAGCGCA
Gymnotus_stenoleucus_2064 TACA-GATCCGGCCCTC-CGGCCGATCAACGAACCAAGTTACCCTAGGGATAACAGCGCA
Gymnotus_sylvius_7239 AATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_sylvius_7240 AATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_tigre_7090 CATA-GATCCGGCC-CC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_tigre_7349 CATA-GATCCGGCC-CC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_ucamara_1927 CATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_ucamara_1950 CATA-GATCCGGCCTCC-CGGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_varzea_2014 TATA-GATCCGGCCCTT-CAGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Gymnotus_varzea_2015 TATA-GATCCGGCCCTT-CAGCCGATCAACGAACCAAGTTACCCAAGGGATAACAGCGCA
Hypopomus_artedi_2232 TACA-GATCCGGCCCC----GCCGATCAACGAACCAAGTTACCCTAGGGATAACAGCGCA
Rhamphichthys_rostratus_2632 GAAA-GATCCGGCCCTT--AGCCGATCAACGAACCAAGTTACCCTAGGGATAACAGCGCA
Sternopygus_astrabes_2203 AAA--GATCCGGCCAC-AAAGCCGATTAACGGACCAAGTTACCCTAGGGATAACAGCGCA
Sternopygus_macrurus_2639 AAAA-GATCCGGCTACTAAAGCCGATTAACGGACCAAGTTACCCTAGGGATAACAGCGCA
Brachyhypopomus_brevirostris_2617 ATCCCCTTTCAGAGTTCCTATCGACGAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Brachyhypopomus_diazi_2408 ATCCCCTTCTAGAGTTCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Brachyhypopomus_diazi_305 ATCCCCTTCTAGAGTTCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Brachyhypopomus_n._sp._PAL_2432 ATCCCCTTCTAGAGTTCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Electrophorus_electricus_2026 ATCCTCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Electrophorus_electricus_2619 ATCCTCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_aff._anguillaris_2091 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
92
Gymnotus_arapaima_2002 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_arapaima_2003 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_ardilai_8175 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_ardilai_8186 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_bahianus_7244 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_bahianus_7245 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_carapo_(CA)_2004 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_carapo_(CA)_2030 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_carapo_(OR)_2040 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_carapo_(OR)_2041 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_carapo_(WA)_2006 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_carapo_(WA)_2007 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_cataniapo_2062 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_cataniapo_2063 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_chaviro_7357 ATCCCCTTCCAGAGTCCCTATCGAC-AGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_chaviro_7358 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_choco_8209 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_coatesi_2042 ATCCCCTCCCAGAGTCCATATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_coatesi_2043 ATCCCCTCCCAGAGTCCATATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_coropinae_(CA)_2010 ATCCCCTCCCAGAGTCCATATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_coropinae_(CA)_2025 ATCCCCTCCCAGAGTCCATATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_coropinae_(GU)_2035 ATCCCCTCCCAGAGTCCATATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_coropinae_(GU)_2036 ATCCCCTCCCAGAGTCCATATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_coropinae_(GU)_2037 ATCCCCTCCCAGAGTCCATATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_coropinae_(GU)_2038 ATCCCCTCCCAGAGTCCATATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_curupira_2009 ATCCCCTTCCAGAGTCCCTATCAACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_curupira_2019 ATCCCCTTCCAGAGTCCCTATCAACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_curupira_2021 ATCCCCTTCCAGAGTCCCTATCAACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_curupira_2024 ATCCCCTTCCAGAGTCCCTATCAACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_cylindricus_2092 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_cylindricus_2093 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_cylindricus_2094 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_henni_7276 ATCCCCTTCCAGAGTCCTTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_henni_7277 ATCCCCTTCCAGAGTCCTTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_henni_8189 ATCCCCTTCCAGAGTCCTTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_henni_8193 ATCCCCTTCCAGAGTCCTTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_henni_8207 ATCCCCTTCCAGAGCCCTTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_henni_8230 ATCCCCTTCCAGAGTCCTTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_henni_8231 ATCCCCTTCCAGAGTCCTTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_javari_2020 ATCCCCTCCCAGAGTCCATATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_jonasi_2016 ATCCCCTCCCAGAGTCCATATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_jonasi_2471 ATCCCCTCCCAGAGTCCATATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_maculosus_8126 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_maculosus_8137 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_maculosus_8169 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_maculosus_8213 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_mamiraua_2012 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_mamiraua_2013 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_n._sp._7104 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_n._sp._7105 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_n._sp._CORU_2558 ATCCCCTTTCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_n._sp._FRIT_7109 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_n._sp._ITAP_2559 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_n._sp._ITAP_7071 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_n._sp._ITAP_7072 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_n._sp._ITAP_7074 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_n._sp._ITAP_7075 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_n._sp._MAMA_7065 ATCCCCTTTCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_n._sp._MAMA_7066 ATCCCCTTTCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_n._sp._MAMA_7067 ATCCCCTTTCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_n._sp._RS1_7088 ATCCCCTTTCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_n._sp._XING_7305 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_obscurus_2017 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_obscurus_2018 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_omarorum_7092 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_omarorum_7093 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_panamensis_8018 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_panamensis_8021 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_panamensis_8210 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_pantanal_7076 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_pantherinus_2039 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_pantherinus_2945 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_pantherinus_7111 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
93
Gymnotus_pedanopterus_2058 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_pedanopterus_2059 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_stenoleucus_2060 ATCCCCTCCCAGAGTCCATATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_stenoleucus_2061 ATCCCCTCCCAGAGTCCATATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_stenoleucus_2064 ATCCCCTCCCAGAGTCCATATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_sylvius_7239 ATCCCCTTTCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_sylvius_7240 ATCCCCTTTCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_tigre_7090 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_tigre_7349 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_ucamara_1927 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_ucamara_1950 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_varzea_2014 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Gymnotus_varzea_2015 ATCCCCTTCCAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Hypopomus_artedi_2232 ATCCCCTTCTAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Rhamphichthys_rostratus_2632 ATCCCCTCCGAGAGTCCCTATCGACAAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Sternopygus_astrabes_2203 ATCCCCTCCCAGAGTCCCTATCGACGAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Sternopygus_macrurus_2639 ATCCCCTCTCAGAGTCCCTATCGACGAGGGGGTTTACGACCTCGATGTTGGATCAGGACA
Brachyhypopomus_brevirostris_2617 TCCTAATGGTGCAGCCGCTATTAAGGGTT-------------------------------
Brachyhypopomus_diazi_2408 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGT------------------------
Brachyhypopomus_diazi_305 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGT------------------------
Brachyhypopomus_n._sp._PAL_2432 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGT----------------------------
Electrophorus_electricus_2026 TCCTAATGGTGTAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAA------------
Electrophorus_electricus_2619 TCCTAATGGTGTAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_aff._anguillaris_2091 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTC---------
Gymnotus_arapaima_2002 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTG--
Gymnotus_arapaima_2003 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_ardilai_8175 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_ardilai_8186 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTA------
Gymnotus_bahianus_7244 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTAC-----
Gymnotus_bahianus_7245 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTAC-----
Gymnotus_carapo_(CA)_2004 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGAT----------------
Gymnotus_carapo_(CA)_2030 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAA------------
Gymnotus_carapo_(OR)_2040 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_carapo_(OR)_2041 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_carapo_(WA)_2006 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGAT----------------
Gymnotus_carapo_(WA)_2007 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGAT----------------
Gymnotus_cataniapo_2062 TCCTAATGGTGTAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAA------------
Gymnotus_cataniapo_2063 TCCTAATGGTGTAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAA------------
Gymnotus_chaviro_7357 TCC---------------------------------------------------------
Gymnotus_chaviro_7358 TCCTAATGGTGTAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_choco_8209 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGA-
Gymnotus_coatesi_2042 TCCTATTGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAA------------
Gymnotus_coatesi_2043 TCCTATTGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGAT----------------
Gymnotus_coropinae_(CA)_2010 TCCTATTGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_coropinae_(CA)_2025 TCCTATTGGTGCAGCCGCTATTAAGGGTTC-T----------------------------
Gymnotus_coropinae_(GU)_2035 TCCTATTGGTGTAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTC---------
Gymnotus_coropinae_(GU)_2036 TCCTATTGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAA------------
Gymnotus_coropinae_(GU)_2037 TCCTATTGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_coropinae_(GU)_2038 TCCTATTGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGAT----------------
Gymnotus_curupira_2009 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_curupira_2019 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_curupira_2021 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCC--------
Gymnotus_curupira_2024 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAA------------
Gymnotus_cylindricus_2092 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_cylindricus_2093 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTG-------------------------
Gymnotus_cylindricus_2094 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTG-------------------------
Gymnotus_henni_7276 TCCTAATGGTGTAACCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_henni_7277 TCCTAATGGTGTAACCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_henni_8189 TCCTAATGGTGTAACCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_henni_8193 TCCTAATGGTGTAACCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_henni_8207 TCCTAATGGTGTAACCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_henni_8230 TCCTAATGGTGTAACCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_henni_8231 TCCTAATGGTGTAACCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTA------
Gymnotus_javari_2020 TCCTATTGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_jonasi_2016 TCCTATTGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_jonasi_2471 TCCTATTGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_maculosus_8126 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGA-
Gymnotus_maculosus_8137 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGA-
Gymnotus_maculosus_8169 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTA------
Gymnotus_maculosus_8213 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTG--
Gymnotus_mamiraua_2012 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_mamiraua_2013 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGAT----------------
94
Gymnotus_n._sp._7104 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_n._sp._7105 TCCTAATGGTGCAGCCGCTA-TAAGGGTTCG-----------------------------
Gymnotus_n._sp._CORU_2558 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_n._sp._FRIT_7109 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_n._sp._ITAP_2559 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_n._sp._ITAP_7071 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_n._sp._ITAP_7072 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_n._sp._ITAP_7074 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCC--------
Gymnotus_n._sp._ITAP_7075 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTA------
Gymnotus_n._sp._MAMA_7065 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_n._sp._MAMA_7066 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_n._sp._MAMA_7067 TCCTAATGGTGCAGCCGCTATTAAGGGTTC------------------------------
Gymnotus_n._sp._RS1_7088 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_n._sp._XING_7305 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_obscurus_2017 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_obscurus_2018 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_omarorum_7092 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_omarorum_7093 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_panamensis_8018 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACA----
Gymnotus_panamensis_8021 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_panamensis_8210 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_pantanal_7076 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_pantherinus_2039 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAA------------
Gymnotus_pantherinus_2945 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_pantherinus_7111 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_pedanopterus_2058 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGT----------------------------
Gymnotus_pedanopterus_2059 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGT----------------------------
Gymnotus_stenoleucus_2060 TCCTATTGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAA------------
Gymnotus_stenoleucus_2061 TCCTATTGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAA------------
Gymnotus_stenoleucus_2064 TCCTATTGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAA------------
Gymnotus_sylvius_7239 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_sylvius_7240 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_tigre_7090 TCCTAATGGTGCAGCCGCTATTAAAGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_tigre_7349 TCCTAATGGTGCAGCCGCTATTAAAGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_ucamara_1927 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAA------------
Gymnotus_ucamara_1950 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGAT----------------
Gymnotus_varzea_2014 TCCTAATGGTGTAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGTCCTACGTGAT
Gymnotus_varzea_2015 TCCTAATGGTGTAGCCGCTATTAAGGGTTCGTTTGTTCAACGAT----------------
Hypopomus_artedi_2232 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTT---------------------------
Rhamphichthys_rostratus_2632 CCCTAATGGTGCAGCCGCTATTAAGGG---------------------------------
Sternopygus_astrabes_2203 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAAGCCCTACGTGAT
Sternopygus_macrurus_2639 TCCTAATGGTGCAGCCGCTATTAAGGGTTCGTTTGTTCAACGATTAAA------------
Brachyhypopomus_brevirostris_2617 --
Brachyhypopomus_diazi_2408 --
Brachyhypopomus_diazi_305 --
Brachyhypopomus_n._sp._PAL_2432 --
Electrophorus_electricus_2026 --
Electrophorus_electricus_2619 CT
Gymnotus_aff._anguillaris_2091 --
Gymnotus_arapaima_2002 --
Gymnotus_arapaima_2003 CT
Gymnotus_ardilai_8175 CT
Gymnotus_ardilai_8186 --
Gymnotus_bahianus_7244 --
Gymnotus_bahianus_7245 --
Gymnotus_carapo_(CA)_2004 --
Gymnotus_carapo_(CA)_2030 --
Gymnotus_carapo_(OR)_2040 CT
Gymnotus_carapo_(OR)_2041 CT
Gymnotus_carapo_(WA)_2006 --
Gymnotus_carapo_(WA)_2007 --
Gymnotus_cataniapo_2062 --
Gymnotus_cataniapo_2063 --
Gymnotus_chaviro_7357 --
Gymnotus_chaviro_7358 CT
Gymnotus_choco_8209 --
Gymnotus_coatesi_2042 --
Gymnotus_coatesi_2043 --
Gymnotus_coropinae_(CA)_2010 CT
Gymnotus_coropinae_(CA)_2025 --
Gymnotus_coropinae_(GU)_2035 --
Gymnotus_coropinae_(GU)_2036 --
95
Gymnotus_coropinae_(GU)_2037 CT
Gymnotus_coropinae_(GU)_2038 --
Gymnotus_curupira_2009 CT
Gymnotus_curupira_2019 CT
Gymnotus_curupira_2021 --
Gymnotus_curupira_2024 --
Gymnotus_cylindricus_2092 CT
Gymnotus_cylindricus_2093 --
Gymnotus_cylindricus_2094 --
Gymnotus_henni_7276 CT
Gymnotus_henni_7277 CT
Gymnotus_henni_8189 CT
Gymnotus_henni_8193 CT
Gymnotus_henni_8207 CT
Gymnotus_henni_8230 CT
Gymnotus_henni_8231 --
Gymnotus_javari_2020 CT
Gymnotus_jonasi_2016 CT
Gymnotus_jonasi_2471 CT
Gymnotus_maculosus_8126 --
Gymnotus_maculosus_8137 --
Gymnotus_maculosus_8169 --
Gymnotus_maculosus_8213 --
Gymnotus_mamiraua_2012 CT
Gymnotus_mamiraua_2013 --
Gymnotus_n._sp._7104 CT
Gymnotus_n._sp._7105 --
Gymnotus_n._sp._CORU_2558 CT
Gymnotus_n._sp._FRIT_7109 CT
Gymnotus_n._sp._ITAP_2559 CT
Gymnotus_n._sp._ITAP_7071 CT
Gymnotus_n._sp._ITAP_7072 CT
Gymnotus_n._sp._ITAP_7074 --
Gymnotus_n._sp._ITAP_7075 --
Gymnotus_n._sp._MAMA_7065 CT
Gymnotus_n._sp._MAMA_7066 CT
Gymnotus_n._sp._MAMA_7067 --
Gymnotus_n._sp._RS1_7088 CT
Gymnotus_n._sp._XING_7305 CT
Gymnotus_obscurus_2017 CT
Gymnotus_obscurus_2018 CT
Gymnotus_omarorum_7092 CT
Gymnotus_omarorum_7093 CT
Gymnotus_panamensis_8018 --
Gymnotus_panamensis_8021 CT
Gymnotus_panamensis_8210 CT
Gymnotus_pantanal_7076 CT
Gymnotus_pantherinus_2039 --
Gymnotus_pantherinus_2945 CT
Gymnotus_pantherinus_7111 CT
Gymnotus_pedanopterus_2058 --
Gymnotus_pedanopterus_2059 --
Gymnotus_stenoleucus_2060 --
Gymnotus_stenoleucus_2061 --
Gymnotus_stenoleucus_2064 --
Gymnotus_sylvius_7239 CT
Gymnotus_sylvius_7240 CT
Gymnotus_tigre_7090 CT
Gymnotus_tigre_7349 CT
Gymnotus_ucamara_1927 --
Gymnotus_ucamara_1950 --
Gymnotus_varzea_2014 CT
Gymnotus_varzea_2015 --
Hypopomus_artedi_2232 --
Rhamphichthys_rostratus_2632 --
Sternopygus_astrabes_2203 CT
Sternopygus_macrurus_2639 --