Chapter 4 Flashcards
Hypothetical common ancestor between fish and tetrapods
Ancestral rhipidistian
General term for diverse group of oldest known vertebrates, extinct
Bony dermal armor of broad plates and smaller tile-like scales, no paired fins
No Jaws- could change pharyngeal shape to draw water in and out
Ostracoderms
Slime eels, marine, scavengers and parasitic, no buccal denticles
Clean whales and farmed for leather
Hagfishes
Buccal funnel with horny denticles and a toungelike cartilaginous rod with horny teeth
Mostly live in fresh water but some are andromedous
Live in sea and mate in water
Lamprey
Placoderms, heavily armored fishes
Extinct
Paired fins *analogues to other fins of fish
Gnathostomes
Covers gills
Operculum
Rat fish
Rat mouth and tail
Wings like a bird
Chimaera- holocephalons
Cartilaginous fishes (bone only in their unique placoid scales and their teeth)
Mouth usually ventral rather than terminal
Chrondrichthyes
What are the 2 types of chondrichthyes
Elasmobranches and holocephalans
Include extinct Paleozoic sharks, modern sharks (squaliformes), plus skates, rays and sawfishes (rajiformes), all have naked gill slits (no operculum) and heterocercal tails
Elasmobranches
What are heterocercal tails
Dorsal fin is longer than ventral fin
Chimaeras
Lack scales, fleshy operculum, upper jaw fused to braincase, bony plates instead of teeth to grind up food
Holocephalans
Member of teleostomi
Oldest Jawed fishes (extinct)
Head and body covered by bony dermal armour
Skeleton of bone and cartilage
Have operculum
Median and paired fins supported by hollow spines
Acanthodians
Member of teleostomi
Bony fishes characterized by having an air sac(lung or swim bladder) and by much dermal bone on the head and shoulder girdle
Group subdivided by structure of paired appendages (ray and lobe fins)
Osteichthyans
Ray finned fishes
True bony fishes w/ membranous fins from basal skeletal elements in body wall, no internal nares, bony operculum, swim bladder often present, blind sac sensory region that does not go into oral cavity
Actinopterygii
Oldest ray finned fishes
Basal actinopterygians
2 types of neopterygians
Part of the ray finned fishes
Holosteans and teleosts
Older group including the gars and bowfins
Holosteans
More recently evolved group, tail not heterocercal, scales less bony and more flexible, Jaws and palate more flexible, pelvic fins farther forward, occupy all aquatic niches 96% of all living fishes, great morphologic diversity
Teleosts
Rhipsidian
Shows where tetrapods may have come from
Lobe fin
Bony fishes, fleshy lobe at base of paired fins, internal nares that invaginates into oral cavity so they can breathe, oropharyngeal cavity, gas filled swim bladder, bony operculum
Sarcopterygii lobe finned fishes
Types of sarcoptergyii lobe finned fishes
Actinistians
Rhipsidians
Dipnoans
Extinct except for the colecanth latimeria
Actinistians
Tetrapod like appendage skeletal elements, amphibian like skull
Rhipsidians
True lung fishes
Dipnoans
Types of amphibia
Labyrinthodonts
Temnospondyls
Microsaurs
Lissamphibians
Lissamphibians
Includes 3 orders of extant amphibians
Apodans
Urodeles
Anurans
Extinct swamp dwellers, tooth dentin was completely folded, many features differed from modern amphibians (bony dermal scales in skin), fishlike tail, primitive fish like skull
Labryinthodonts
Extinct, some members had skeletal similarities to modern frogs and salamanders
Temnospondyls
Fossil forms with skeletal features of caecilians (burrowers)
Microsaurs
Limbless caecilians
No feet
Apodans