week 3: b. classes of fishes lamprey chondrichthyes osteichthyes
TRANSCRIPT
Week 3:
B. Classes of Fishes
LampreyChondrichthyesOsteichthyes
Chondrichthyes~1000 species
sharks
rays
chimaeras
Holocephali
Elasmobranchii
shark
body shapepectoral fingill placementanal fin
ray
Elasmobranchs
Sharks~400 species
5th
superorder
Sharks
Galea (with anal fin) ~280 species
Squalea (mostly no anal fin) ~120 species
Phylum Chordata Class Chondrichthyes
Subclass Holocephali Order Chimaeriformes
Subclass Elasmobranchii
Division Selachii (text: Superorder Galea)
Order Orectolobiformes
Order Lamniformes
Order Carcharhiniformes
Division Batoidea (text: Superorder Squalea)
Order Rajiformes
Order Myliobatiformes
1.
Week 3 sharks...
Orectolobiformes~33 sp with terminal mouth
Lamniformes~ 15 sp. with subterminal mouth
Carcharhiniformes ~ 225 sp with subterminal mouth and nictitating eyelid
Carcharhiniformes
subterminal mouthnictitating membrane
nictitating membrane
cat sharks
NEAq 2010: coral, chain
Carcharhiniformes
Scyliorhinidae~160 sp.
oviparous
keratin egg case
1-2 m>20 y captivitylarge interspecific schools along Calif. coastovoviviparous ~30 pups/litter
Carcharhiniformes
Triakidae~40 sp.
hound sharks
Triakis semifasciataleopard shark
requiem sharks
Carcharhiniformes
Carcharhinidae Carcharhinus~30 sp.
~no spiracles~ram ventilators~viviparity
black-tip reefCarcharhinus melanopterus1.5 m
interspecific schoolingelaborate displayshierarchies
oceanic whitetipCarcharhinus longimanus
pelagic scavenger at ship and plane wrecks
silky shark Carcharhinus falciformeswith pilot jacks
aggressiveschools with tunabycatch
grey reef shark Carcharhinus amblyrhynchoides ~25 years
black tip reef shark Carcharhinus melanopterus
blacktip shark Carcharhinus tilsoni
inshore spinner
bull shark Carcharhinus leucas
freshwater spinner2-3 m length
also Mississippi, NAZambezi, AfricaLake Nicaragua, CA
Amazon River Valley
freshwater ~2000 mile migration
lemon sharkNegaprion brevirostris
color visionmature 24 ylife-span 30 yreplace teeth ~ 8 days3 m long
Carcharhinidae
low oxygen, salinity
fast-growingmatures 4-6 ylives~12 y
long labial furrows
nocturnalsolitaryonly ovoviviparous carcharhinid10-80 pups/litter
blue shark Prionace glauca
widest rangingmigratory > 6000 km/yr, 60 km/dayspeeds 30 km/h
Carcharhinidae
no spiracles
mating woundsfemale skin 3x thicker than male skin and teeth
segregated schools
aggressive
~13 ft~20 y
threatenedmost heavily fished~bycatchfinned, discarded
50,000/yroff Hawaii6 M/yr global
from Costa Rica
Traditional Chinese Medicine (TCM)
IUU illegal, unregulated, unreported
to Singapore
CarcharhiniformesSphyrnidae
hammerheads
stereoscopic detection
triangulation
manueverability
acute vision, chemical and electrical detection
~8 species
winghead
scoophead
scalloped
great hammerhead
mallethead
small eye
bonnethead
smooth
large schools near magnetic mounts
bycatchhigh mortality
viviparity
placental viviparity~4 month gestation
~parthenogenesis
Carcharhiniformes
subterminal mouthnictitating membrane
Week 3 sharks...
Orectolobiformes~33 sp with terminal mouth
Lamniformes~15 sp. with subterminal mouth
Carcharhiniformes ~ 225 sp with subterminal mouth and nictitating eyelid