Subphyllum Vertebrata
MYXINIDAE.
(Hagfishes, 32 spp).
*Dorsal fin absent.
*Caudal fin extends onto part of dorsal surface.
*Eyes are degenerated.
*Barbels present around biting mouth.
*Teeth only on tongue, plus one on “palate”.
*No spiral valve or cilia in intestinal tract.
*Numerous mucous pores along the body.
*Ovaries and testis in the same individual but only one functional (not hermaphrodite).
*Scavemger feeders.
Subphyllum Vertebrata
petromyzontidae
(Lampreys, ± 110 spp).
*Anadromus and freshwater; cool zones in the world.
*One or two dorsal fins are present.
*Eyes well developed in adults and barbels absent
*Teeth on oral disc and tongue.
*Spiral valve and cilia in intestine tract.
*Larva stage “ammocoete” under radical metamorphosis in fresh water.
*Lampreys have 164-168 chromosome (highest number in a vertebrate).
Subphyllum Vertebrata
CHIMARIDAE.
(Ratfish or shortnose chimaeras, ±20 spp).
*Marine, Atlantic and Pacific.
*Snout short and rounded.
*Tail diphycercal.
*A poison gland is associated with dorsal spine.
*Venom is painful for humans.
Subphyllum Vertebrata
Superorder Euselachii
HETERODONTIDAE
(Bullhead, horn or Port Jackson sharks , 8 spp).
*Marine, tropical indian and Pacific.
*Two dorsal fins with spines.
*Anal fin present.
*Five gill slits.
Subphyllum Vertebrata
Superorder Euselachii
Order Carcharhiniformes
Sphyrnidae
(Hammerhead sharks, 9 spp).
*Marines, occasionally brackfish; all oceans.
*Lateral expansion of the head.
*Spiracle absent.
*Eyes and nasal openings farther apart than other sharks.
Subphyllum Vertebrata
Superorder Euselachii
SQUALIDAE.
(dogfish shark ± 71 spp).
*Marine, Atlantic, Indian and Pacific.
*Snout not produced into a flat blade and without lateral teeth or barbels.
*Five gill openings, all anterior to the pectoral fin.
Several memebers in the family are luminescent.
Subphyllum Vertebrata
Superorder Euselachii
pristiophoridae
(Saw sharks , 8 spp).
*Marine, South Africa and Indo-Pacific.
*Snout produce in a long flat blade with teeth on each side.
*Teeth unequal in size, usually alternating large and small.
*One pair of long barbels.
*No dorsal fin spine.
Subphyllum Vertebrata
Superorder Euselachii
(Angel sharks, 11 spp).
*Marines, Atlantic and Pacific.
*Two spineless dorsal fins.
*No anla fin.
*Five gill openings.
*Mouth almost terminal.
*Nostrils terminal with barbels on anterior margin.
Subphyllum Vertebrata
Superorder Euselachii
CARCHARHINIDAE.
(Smooth dogdfishes, requiem sharks ± 91 spp).
*Marine, All oceans.
*Fifth gill opening over or behind origin of pectoral fin.
*Two subfamilies; in this jar is the subfamily Triakinae (smooth dogfishes).
*Dog fishes has teeth usuallly low with three or more cusps
Subphyllum Vertebrata
Superorder Batidoidimorpha
TORPEDINIDAE
(Electric rays , ± 38 spp).
*Power electric organs, derived from banchial muscles in the heas region.
*Skin soft and loose.
*Eyes small to obsolete.
*Caudal fin very well developed.
*Dorsal fin 0-2
Subphyllum Vertebrata
Superorder Batidoidimorpha
RHINOBATIDAE
(Guitarfishes ± 48 spp).
*Marines, Atlantic, Indian and Pacific.
*Body intermediate between sharklike and skatelike.
*Tail stout. Not definitely marked off body.
*Two distinct dorsal fins and a caudal fin.
*Denticles over body form a row on midline of back.
*Tail without spine.
Subphyllum Vertebrata
Superorder Batidoidimorpha
Order Rajiformes
RAJIDAE.
(Skates, ± 190 spp).
*Marine, All oceans.
*Caudal fins reduced or absent.
*Tail extremely slender.
*Weak electric organs derived from caudal muscles.
*Dorsal fin 0-2.
*Most with prickles on skin, often with a row along midline of back..
Subphyllum Vertebrata
Superorder Batidoidimorpha
DASYATIDAE.
(Stingrays , ± 90 spp).
*Outer anterior margin of pectoral continuous along side of head.
*No separate cephalic or subrostral fins.
*No distinct dorsal fin.
*Most species with one or more long poisonous spines on tail.
Subphyllum Vertebrata
Superorder Batidoidimorpha
GYMNURIDAE
(Buterfly rays ± 30 spp).
*Marines, Atlantic, Indian and Pacific.
*Disc extremely broad, more than 1.5 as broad as long.
*No caudal fin.
*Tail short (distancefrom cloaca to tip much shorter than breadth of disc..
Subphyllum Vertebrata
Order Lepidosireniformes
PROTOPTERIDAE.
(African Lungfishes, 4 spp).
*Freshwater, Africa..
*Six gill arches.
*Five gill clefts.
*Body moderately elongate.
*One genus.
Subphyllum Vertebrata
LEPISOSTEIDAE.
(Gars , 7 spp).
*Freshwater, rare marine. North, central America and Cuba.
*Body and jaws enlongate.
*Mouth with needlelike teeth.
*Abbreviated heterocercal tail.
*Heavy ganoid scales.
*Dorsal fin far back with few rays.
*No gular or interopecular.
*Swim bladder vascularized.
Subphyllum Vertebrata
Order Acipenseriformes
POLYODONTIDAE.
(Paddlefish, 2 spp).
*Freshwater, USA and China.
*Snout paddlelike.
*Body naked except for a few scaleson caudal peduncle.
*Minute barbel on snout.
*Gill rakers long.
*Teeth minute.
*Spiracle present.
*gill cover greatly produced posteriorly.
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