B4 Vertebrates Flashcards
Class Actinopterygii
26,891 living species, sister group to Sarcopterygii. Monophyletic, with no strong derived characteristics (scales, spiracle and gular plate absent).
Subclass Neopterygii
everything else, ancient. Has two orders (Lepisosteiformes, Amiiformes)
Subclass Chondrostei
27 species (looks like fat bottom-feeder shark), sturgeons or paddle fish. Silurian. cartilaginous skeleton, spiracle, epidermal tail. Ancient.
Fish fins
Bony elements to support each fin ray.
Subclass Cladistia
16 species (looks like fat aquatic lizard), 5-7 small fins alone spine, can walk on land. Ancient.
Division Teleostei (‘true bony fish’)
Everything else. 26,840 species. Mobile premaxilla, neural arches on dorsal side of tail base (uroneural bones). Ventral pharyngeal tooth plates unpaired, particular arrangement of skull bones.
Order Lepisosteifomes (Gars)
7 species. Rays goo all the way down but still have bony structure, almost epicarcal tail. Predatory fish, long, from Americas, often survive in low oxygen water due to gas bladder.
Subdivision Osteoglossomorpha (of Teleostei)
Includes bony tongues, featherkin knifefishes, elephantfishes (large brains, learning capacity), gymnarchids (electric field detects environment).
Subdivision Eluteleostei (of Teeostei)
Majority of fish species. 17,422.
Shark fins
Supporting elements like basal cartilage.
Order Amiiformes (Bowfin)
1 species, spiral valve intestine like sharks. Bony plate on lower jaw, kind of epidermal tail.
Subdivision Otocephala
Otophysic, connection from gas bladder to ear, good hearing.
Superorder Ostariophysi
7,890 species (68% of all FW fishes). Sophisticated chemical alarms which alert other fish in school to injury or attack. Includes minnows, carps, loaches, suckers, tetras, piranhas (no signal). Connect gas bladder to ear via Weberian system. (groups: cyprinids, characins, catfishes, knifefishes).
Superorder Clupeomorpha
364 species, mainly marine, includes herrings, anchovies, shads. Very abundant, and commercially important.
