Acipenseriformes: spiracles heterocercal caudal fin Cartilaginous skeleton (secondary) spiral valve Actinopterygii Euteleostomi Class Actinopterygii, Subclass Chondrostei, Order Acipenseriformes, Sturgeon and Paddlefish Most primitive ray-finned fishes Largely cartilagenous skeleton Spiral valve Heterocercal tail Bony scutes and plates Snout No branchiostegal rays Spiracles Family Acipenseridae, 4 genera, 24 species Class Actinopterygii, Subclass Chondrostei, Order Acipenseriformes, Sturgeon and Paddlefish Diadramous, anadramous, land locked populations Long lived Protrusable mouth Asian species 28 feet, 2800 lbs Commercial fisheries peaked ~1890 meat, caviar, oil Life history Spawning in Bouie River. Summer/Fall holding area in Pascagoula River Seaward migration in late fall. Habitat requirements (large rivers) 1
Class Actinopterygii, Subclass Chondrostei, Order Acipenseriformes, Sturgeon and Paddlefish Polydontidae - paddlefish 2 living species No scutes, reduced scales Upper jaw bones fused Feeding Ecology Egg scatterers, no parental care Paddle function? Conservation loss of floodplain habitat, impoundments Psephurus gladius Chinnese paddlefish, one specimen caught in 2007, one in 2003. Most likely extinct. Class Actinopterygii, Infraclass Neopterygii, Order Lepisosteiformes, gar 7 species in one living family, Actinopterygii Chondrostei bichir and sturgeon Neopterygii all others North and Central America Neopterygii Holostei Bowfin and Gars Teleostei all others Mostly ossified skeleton, bony plates cover cartilageouns skull Vertebrae are opisthocoelous Ganoid scales Reduced heterocercal tails Facultative air breathers 2
Class Actinopterygii, Infraclass Neopterygii, Order Lepisosteiformes, gar Unique larval notocord function Toxic eggs Conservation concern Dearth of ecological information Atractosteus tropicus; tropical gar Atractosteus spatula; alligator gar Lepisosteus osseus; longnose gar Lepisosteus oculatus; spotted gar Atractosteus tristoechus; Cuban gar Lepisosteus platostomus; shortnose gar Lepisosteus platyrhincus; Florida gar Atractosteus 3 species Lepisosteus 4 species Class Actinopterygii, Order Amiiformes, bowfin 1 extant species Ganoid scales Reduced heterocercal tails Undulating dorsal fin Single gular plate Eastern North America Ocellus in juveniles and reproducing males Parental care Class Actinopterygii,Order Amiiformes, bowfin Cycloid scales Canine like teeth, strong jaws Single lung (2 lobes) Aquatic/aerial respiration Aestivation? Abundant in swampy areas and oxbow lakes 3
Actinopterygii Chondrostei bichir and sturgeon Neopterygii all others Neopterygii Holostei Bowfin and Gars Teleostei all others Teleostei 60 orders Ctenoid, cycloid or ganoid scales Lack paired gular plate & most lack any gular plate Branchiostegal rays present Homocercal caudal fin Lack spiral valve in intestine Subdivision Elopomorpha 4 orders Elopiformes - tenpounders Albuliformes - bonefishes Anguiliformes - eels Notacanthiformes spiny eels 24 families, 156 genera, 856 species 4
Subdivision Elopomorpha, Order Elopiformes Tenpounders, ladyfish and tarpons Compressed body Deeply forked caudal fin Large gular bone Maxilla part of gape two upper jaw biting bones Record fecundity 12 million eggs Marine, shallow tropical regions Subdivision Elopomorpha, Order Albuliformes Bone Fishes Small group, 12 species in two genera. Subdivision Elopomorpha, Order Anguilliformes Subdivision Elopomorpha, Order Anguilliformes Eels 738 species, 141 genera, 15 families shallow water, except Nemichthyidae marine (except Anguillidae), tropical to temperate Nemichthyidae Anguilidae Sackpharynx fishes, gulpers, swallowers Arguably the most anatomically different vertebrates Muraneidae Congridae 5
Subdivision Elopomorpha, Order Anguilliformes, Anguilidae Freshwater eels Subdivision Elopomorpha, Order Anguilliformes, Anguilidae Freshwater eels Pectoral fins present Mostly catadromous Most benthic, adapted to getting into/out of crevices American and European eels once thought to be same species Population structure within species not clear how do they know where to go? Conservation Fishery - Eel larvae Size distribution of american ell larvae Size distribution of European ell larvae Elvers sold to Asian markets for up to $2000 a pound Not clear if fishery is sustainable Catadramous and semelparous 6