body morphology
heterocercal caudal fin
- elongated dorsal lobe
scale evolution
ganoid -> ctenoid -> cycloid
hetero caudal fin
heterocercal - no protrusible jaw - ganoid scales
myxopterygia
male claspers seen in chondrichthyes
unpaired fins
medial, median fins
notochord
seen in lamprey and hagfish - seen in vertebrae: only in embryo and transforms becoming ossified vertebrae
ctenoid scales
thin flexible and overlapping scales in bony fish that have tiny spines feels more like sandpaper in most bony fishes
cosmoid scales
"cosmine"
electrosensory system in chondrichthyes
- convergent evolution analogous in many species
rudimentary/simplified soft rays
- dorsal ray formula: lower case roman numeral for spine - end/beginning of soft rays wo branching
dentition and replacement teeth in Carcharhinidae
- jaw symphysis
intracranial joint
- movable joint in cranium (moves mouth open more) - phylogenetic link of early tetrapods and sarcopterygii - only seen in Celecante fish species
premaxillae mobile
- relative to cranium - enhanced suction feeding
gill cover (operculum)
Bony cover that protects the gills.
dorsal ray formula
D XI, 1 D: anatomical feature - D: dorsal - V: pelvic - P: pectoral - A: anal roman numeral: number of spines arabic numeral: number of soft rays
anguilliform
EX. eel
depressiform
EX. skate
compressiform
EX. sunfish
gill filaments
Fingerlike projections through which gases enter and leave the blood system-used for respiration
lateral line
a faint line visible on both sides of a fish's body that runs the length of the body and marks the location of sense organs that detect vibrations in water
positions of pelvic fins
abdominal thoracic jugular subjugular
ethmoid portion
anterior part of cranium
urostyle
bone connecting sacral vertebrae
ceratotrichia
flexible rays of horn-like protein seen in chondrichthyes
body forms
fusiform compressiform depressiform anguilliform
pseudobranch
gill-like epithelium located on the underside of the operculum not in all species
hyomandibular
important for function of jaw and neurocranium
choanae
internal nostrils homologous w tetrapods
gill membranes
isthmus: attached/not to gill membranes
paired fins
lateral/bi-lateral
hyoid apparatus
located to the sides of arches ventilation of respiratory flow
first arch in gills
most anterior - pharyngobranchial - epibranchial - ceratobranchial - hypobranchial - basibranchial
spiny fins
no striations/segmentation solid bone
jaw anatomy
pharyngobranchial & ceratobranchial: paired basibranchial: unpaired
gill rakers
projections along the inner surface of fishes' gills used for filter-feeding
branchial arches
respiratory structure
barbels
seen on the chin/ around mouth paired & unpaired sensory structure
soft ray fins
segmented and branched held together by membrane
fusiform
slightly elongated, compressed side-to-side EX. tuna
evolution of jaws from anterior gill arches of a jawless ancestor
spiracle - assists w ventilation - for benthic cartilaginous fishes - well developed in stingrays, skates
cycloid scales
thin, overlapping scales with a smooth posterior edge in most bony fishes sometimes have canals/lateral lines with pores
caudal fin rays
type of soft ray located most posterior part of body (tail)
adipose fin
unpaired tab of soft tissue wo rays/spines small nub between dorsal & caudal fin area on back