Page 1 Flashcards
Superclass Agnathans
Order Myxiniformes - hagfishes
Family Myxinidae
Order petromyzontiformes - lampreys
Family petromyzontidae
No fins
Oviparous
Cartilaginous skeleton
Myxiniformes
Single median nostril Saprophytic Produce mucus Mouth a circular sucking disc, no jaws Barbel around mouth and nostril 10-14 gill pores each side 1 semicircular canal Large eggs
Petromyzontiformes
Mouth circular sucking disk with horny teeth, no jaws 7 gill pores each side Single median nostril No barbels 2 semicircular canals Small eggs
Superclass Gnathostomata Class Chondrichthyes Subclass Elasmobranchs
Order Heterodontiformes
Family Heterodontidae - horn sharks
Order Squaliformes
Family Squalidae - dogfish sharks
Order Carcharhiniformes
Family Carcharhinidae - requiem sharks
Order Myliobatiformes
Family Dasyatidae - stingrays
Order Rajiformes
Family Rajidae - skates
Family Rhinobatodae - guitarfishes, thornbacks
5-7 gill slits Placoid scales 3 semicircular canals No gas bladder, large liver with oil Jaws protrusion flexible and cartilagenous Spiracle and spiral valve
Order Heterodontiformes
A fin present 2 D fins each with fixed spines Heterocercal C fins Egg in horny case surrounded by spiral fluting 2nd set of molars for crushing
Order Squaliformes
2 D fins with spines
No A fins
No keep in C fins
Origin of 1st D behind P1
Order Carcharhiniformes
2 D without spines Long p1 fins Nictitating membrane No keel in C Blade like teeth with a single cusp
Order Myliobatiformes
Tail long, armed with one to several saw edged, venomous spines
Outer edge of p2 fins convex
No D fin
Order Rajiformes
Family Rajidae Two very small D fins near tail Outer edge of p2 convex No tail spines Diamond shaped
Family Rhinobatidae C not bilobed 2 D fins Origin of 1st D behind p2 No venomous spines
Class Chondrichthyes Subclass Holocephali
Order Chimaeriformes
Family Chimaeridae - ratfishes
Skin flap covering gill opening each side
Holystic jaw suspension
No scales or spiracle
Gill filaments free at tips like bony fishes
P1 large, p2 set far back under/behind tips of p1
Jaw teeth in plates
Single strong spine on front D fin
Lateral line very electrosensitive
Class Sarcopterygii Subclass Dipnoi
Order Lepidosireniformes
Family Protopteridae - African lungfishes
Body elongate, compressed, snout blunt and eel like
A and D fins confluent around tail
P1 and p2 fins long, slender, filamentous and rod like
Tooth plates in mouth
Can breathe air
Form cocoons of mucus
Class Actinopterygii Subclass Chondrostei
Order Polypteriformes
Family Polypteridae - bichirs and reed fishes
Order Acipenseriformes
Family Acipenseridae - sturgeons
Family Polyodontidae - paddle fishes
Order Polypteriformes
D fin divided into series of finlets Heavy paleoniscoid ganoid scales Gular plate present Base of p1 fins fleshy, lobe like with low p1 and p2 Paired lungs
Order Acipenseriformes
Family Acipenseridae 5 widely separated rows of pointed bony plates Heterocercal C fin Transverse row of 4 barbels below snout Cartilaginous skeleton Ganoid scales only on tail
Family Polyodontidae
Snout extremely elongate, flattened, spatular with electroreceptors
Heterocercal C fin
2 minute barbels on lower posterior surface of snout
Cartilaginous skeleton with only few small scales on C fin
