Searching for the Marine Relatives of Neotropical Freshwater Stingrays

Florian Reyda1, and Fernando Marques2

1Biology Department and Biological Field Station, SUNY Oneonta 2University of Sao Paulo, Brazil

The proposed work is to conduct a biotic survey of the tapeworms of stingrays from the eastern Pacific Ocean and the Caribbean Sea, and then to compare those species to those in South America and elsewhere. Previously, we conducted studies with colleagues and students on the tapeworms of South American freshwater stingrays (i.e.,potamotrygonids; see figure on lower left) in order to build a robust taxonomic framework in in which hypotheses of species boundaries and inter-relationships (see figure on lower right) were based on both morphological (light and scanning electron microscopy) and molecular (DNA sequence) data. These data, when combined with a growing body of data on elasmobranch tapeworms from across the globe (see Tapeworms.uconn.edu) will enable us to determine the phylogenetic position of the species we encounter in this project. Ultimately, we will test the hypothesis that the closest living relatives of potamotrygonid tapeworm species are those that occur in stingrays in the eastern Pacific and the Caribbean.

Rhinebothrium fulbrighti

Rhinebothrium brooksi

Rhinebothrium copianullum

Rhinebothrium paratrygoni

Sampling rationale: We have chosen to focus on the eastern Pacific and Caribbean because those are the hypo- thesized areas of derivation of potamo- trygonids and their tapeworm parasites. We will investigate all tapeworm species we encounter, but will focus on species of the genera Acanthobothrium and Rhinebothrium (see figure above).

Acanthobothrium (A) & Rhinebothrium (B)

Acknowledgments: Thanks to J. Caira and K. Jensen for leading a global-scale effort to further the knowledge of tapeworms, and for the Global Cestode Database. Initial fieldwork for this project is being funded by the SUNY Oneonta Research Foundation and by the Brazilian agency FAPESP.

Broader Impacts: The proposed work will lead to an increased knowledge

of biodiversity in Peru, Panama, and Venezuela. The results may serve as a potential model system for future studies of host-parasite coevolution. It will also lead to

continued collaborations between two international groups of researchers.

1

1Biology Department and Biological FieldB2Unive

Rhinebothrium fulbrighti

Rhinebothrium brooksi

Rhinebothrium copianullum

Rhinebothrium paratrygoni

A) & Rhinebothrium (B)