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Lab 2 Fish Evolution and Wisconsin Fish Families. Lecture Major taxonomic groups Functional and anatomical evolution Nomenclature Lab Compare traits of families Identification of Wisconsin fishes to family level Start taxonomic key assignment. Evolution of Major Groups of Vertebrates
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Lab 2Fish Evolution and Wisconsin Fish Families • Lecture • Major taxonomic groups • Functional and anatomical evolution • Nomenclature • Lab • Compare traits of families • Identification of Wisconsin fishes to family level • Start taxonomic key assignment
Evolution of Major Groups of Vertebrates The width of the branches indicate the relative number of recognized genera for a given time level on the vertical axis. Time in millions of years. Cartilaginous Fishes Hagfishes Lampreys Teleosts Amphibians Birds Mammals Reptiles Cenezoic 425 Cretaceous 135 Jurassic 180 Triassic 230 Permian 280 Carboniferous 345 Devonian 400 Silurian 425 Ordivician 500 Cambrian 570
Evolution of Major groups of Fishes The width of the branches indicate the relative number of recognized genera for a given time level on the vertical axis. Time in millions of years. Latimeria Bowfin Hagfishes Lampreys Sharks Rays Bichir Sturgeons Gars Teleosts Chimaeras Cenezoic 425 Cretaceous 135 Jurassic 180 Triassic 230 Permian 280 Carboniferous 345 Devonian 400 Silurian 425 Ordivician 500 Cambrian 570 Lungfish
Taxonomic Nomenclature • Kingdom – Animalia • Phylum – Craniata • Class – several • Order – in fishes, always ends with -iformes • Family – in fishes, always ends with -idae • Genus – complex nomenclatural conventions • Species – complex nomenclatural conventions
Jawless FishesSuperclass: Agnatha500 mybp • Jawless (agnathous) • Bony armor • Muscular feeding pump
Jawless Fishes Hagfishes (Order: Myxiniformes) • Notochord (no vertebrae) • Cartilaginous cranium • 30-35 extant species • Harvested commercially
Jawless FishesLampreys (Order: Petromyzontiformes) • Cartilaginous skeleton • Dorsal, anal, and caudal fins • Lateral line system • Well-developed eyes
Jawed FishesSuperclass: Gnathostomata400 mybp • Composed of: • Sharks and their kin (Class: Chondricthyes) • Lobe-finned fishes (Class: Sarcopterygii) • Ray-finned Fishes (Class: Actinopterygii) longnose gar (Lepisosteus osseus)
Jawed FishesClass: Chondrichthyes • Sharks, rays, chimaeras • 850 extant species • Cartilaginous skeleton • Placoid scales • Spiral valve intestine
Bony FishesClass: Osteichthyes • Diverse assemblage • Lungs or swimbladder • Bony skeleton
Lobe-Finned FishesClass: Sarcopterygii Lemur • Characterized by fins with bony, leg-like supports • Coelacanths (Subclass: Coelacanthimorpha) • Lungfishes (Subclass: Dipnoi) • Tetrapods arose from Sarcopterygians Latimeria Neoceratodus
Ray-finned fishesClass: Actinopterygii • Characterized by improved scales, pelvic and pectoral girdles, jaws, swim bladders, and branchiostegal rays • Fins attached by rays • Contains 96% of all living fish species (>25,000) • Sturgeons, paddlefishes, bichirs and reedfish (Subclass: Chondrostei) 390 mybp • Gars and bowfin (Subclass: Neopterygii) 225 mybp • All true bony fishes (Division: Teleostei) bowfin (Amia calva) lake sturgeon (Acipenser fulvescens) ornate bichir (Polypterus ornatipinnis)
True Bony FishesDivision: Teleostei130 mybp • Characterized by cycloid or ctenoid scales, three or four lower jaw bones per side, increased cranial complexity, swim bladders (usually) • Compose 95% of all extant species (~24,000) • Four subdivisions: • Osteoglossomorpha (Bony tongues) • Elopomorpha (Tarpons, eels) • Clupeomorpha (Herrings) • Euteleostei (Teleosts)
Bony tonguesSubdivision: Osteoglossimorpha • Composed of one Order: Osteoglossiformes • Bonytongues (Superfamily: Osteoglossidae) • Mooneyes, featherbacks, and knife fish (Superfamily: Notopteridae) • Elephant fish (Superfamily: Mormyroidei) Mooneye(Hiodon tergisus) Boulengeromyrus knoepffleri Arapaima Arapaima gigas
Tarpon, EelsSubdivision: Elopomorpha • Characterized by leptocephalus larvae • Tarpons, ladyfish (Order: Elopoformes) • Bonefish (Order: Albuliformes) • Eels (Order: Anguilliformes) leptocephalus bonefish (Albula vulpes) Two eels tarpon (Megalops atlanticus)
HerringsSubdivision: Clupeomorpha • 4 Families (2 are well known) • Herrings, shads, sardines and menhaden (Family: Clupeidae) • Anchovies (Family: Engraulidae) • Characterized by a connection between the swim bladder and the ear bay anchovy (Anchoa mitchilii) alewife (Alosa pseudoharengus)
TeleostsSubdivision: Euteleostei • 30 orders, 374 families, >3,500 genera, >19,000 Species • Poorly characterized • We’ll focus on 4 Euteliost superorders: • Ostariophysi • Protacanthopterygii • Paracanthopterygii • Acanthopterygii
Superorder: Ostariophysi • Dominate continental freshwaters • Minnows, carps, and suckers (Order: Cypriniformes) • Catfishes (Order: Siluriformes) Northern hog sucker (Hypentelium nigricans) Common carp (Cyprinus carpio) White sucker (Catostomus commersoni) Black bullhead (Ictalurus melas)
Superorder:Protacanthopterygii • Popular commercial and recreational fish • 320 species worldwide • Pikes, mudminnow (Order: Esociformes) • Salmon, trout, whitefish (Order: Salmoniformes) • Smelt (Order: Osmeriformes) Cisco (Coregonus artedi) Brook trout (Salvelinus fontinalis) Northern pike (Esox lucius) Rainbow smelt (Osmerus mordax)
Superorder:Paracanthopterygii • Oddballs in Wisconsin • Trout-perch, pirate perch (Percopsiformes) • Burbot (Gadiformes) Trout-perch (Percopsis omiscomaycus) Pirate perch (Aphredoderus sayanus) Burbot (Lota lota)
Superorder: Acanthopterygii • Most speciose superorder among vertebrates • Killifish (Order: Cyprinidontiformes) • Silversides (Order: Atheriniformes) • Sticklebacks (Order: Gasterosteiformes) • Sculpins (Order: Scorpaeniformes) • Bass, sunfish, perch, darters, drum (Order: Perciformes) Brook stickleback (Culea inconstans) Mottled sculpin (Cottus bairdi) Rainbow darter (Etheostoma caeruleum) Blackstripe topminnow (Fundulus notatus) Brook silverside (Labidesthes sicculus) Pumpkinseed (Lepomis gibbosus)
Major Trends in Fish Evolution • Increased cranium and jaw sophistication • Branchiostegal rays • Maxilla separation • Increased efficiency of movement • Loss of external armor • Fin placement and morphology • Air bladders • Simplification of skeletal system
Branchiostegal Rays • Maintains a flexible seal between operculum and body as oral cavity expands • Increases efficiency of respiration and allows for suction feeding
MX PM Advances in Fish Feeding Mechanisms “Primitive” PM MX “Derived”
Advances in Fish Feeding Mechanisms Brook trout – primitive, maxilla included in gape Largemouth bass – derived, maxilla excluded from gape
Largemouth Bass Jaw ProtrusionDecreases distance between predator and preyIncreases the amount of suction force generated PM PM MX MX
Loss of external armor Shovelnose sturgeon Channel catfish
Movement of Pelvic Fins From Abdominal to Thoracic Position “Primitive” “Derived” Abdominal Position Thoracic Position
Caudal Fin Evolution Heterocercal caudal fin Homocercal caudal fin
Air Bladders • Lungs evolved before air bladders • Two types of air bladders: • Physostomous • Connected to the foregut by the pneumatic duct • On many primitive fish • Physoclistous • Detached from the gut, inflated through gasses in the blood • On many derived fish
Vertebrae Simplification caudal abdominal Primitive condition (60-75 vertebrae) 2/3 1/3 caudal Intermediate condition abdominal 1/2 1/2 abdominal caudal Derived condition (24 vertebrae) 2/3 1/3
Bowfin (Amia calva), photo by John Lyons Giant snakehead
Compare these fishes Giant snakehead (Channa micropeltes) Bowfin (Amia calva)