Fish Taxonomy
KINGDOM ANIMALIA
PHYLUM CHORDATA
SUPERCLASS AGNATHAClass Myxini (1 order)Class Cephalaspidomorphi (1 order)
SUPERCLASS GNATHOSTOMATAClass Chondrichthyes (10 orders)Class Sarcopterygii (3 orders)Class Actinopterygii (4 orders) Division Teleostei (35-38 orders)
KINGDOM ANIMALIAPHYLUM Chordata
SUPERCLASS AgnathaClass Myxini (1 order)Class Cephalaspidomorphi (1 order)
SUPERCLASS Gnathostomata
Class Chondrichthyes (10 orders)
Class Sarcopterygii (3 orders)
Class Actinopterygii (4 orders) Division Teleostei (35-38 orders)
SUPERCLASS AGNATHAClass MyxiniOrder Myxiniformes (hagfishes)Class Cephalaspidomorphi Order Petromyzontiformes (lamprey)
SUPERCLASS GNATHOSTOMATAClass Chondrichthyes Subclass Holocephali Order Chimaeriformes (chimaeras) Subclass Elasmobranchii9 orders (sharks, rays, skates)Class Sarcopterygii Subclass CoelacanthimorphaOrder Coelacanthiformes (coelacanths) Subclass DipnoiOrder Ceratodontiformes (Australian lungfish)Order Lepidosireniformes (S. American, African lungfish)Class Actinopterygii - (rayfins, higher bony fishes) Subclass ChondrosteiOrder Polypteriformes (birchirs, reedfish)Order Acipenseriformes (sturgeons, paddlefishes) Subclass NeopterygiiOrder Semionotoformes (Lepisosteiformes) (gars)Order Amiiformes (bowfin) Division Teleostei35-38 orders (modern body fishes)
SUPERCLASS AGNATHA
Class Myxini
Order Myxiniformes (hagfishes)
Class Cephalaspidomorphi
Order Petromyzontiformes (lamprey)SUPERCLASS GNATHOSTOMATA
Class Chondrichthyes Subclass Holocephali
Order Chimaeriformes (chimaeras) Subclass Elasmobranchii
9 orders (sharks, rays, skates)Class Sarcopterygii Subclass Coelacanthimorpha
Order Coelacanthiformes (coelacanths) Subclass Dipnoi
Order Ceratodontiformes (lungfish)Order Lepidosireniformes (S. American, African lungfish)
Class Actinopterygii - (rayfins, higher bony fishes) Subclass Chondrostei
Order Polypteriformes (birchirs, reedfish)Order Acipenseriformes (sturgeons, paddlefishes)
Subclass NeopterygiiOrder Semionotoformes (Lepisosteiformes) (gars)Order Amiiformes (bowfin)
Division Teleostei35-38 orders (modern body fishes)
Bond pp. 77-87
• Jawless - feed through sucking mouthparts
• Gill openings are pores, not slits
• No paired fins
• Silurian/early Devonian periods (440-400 MYA)
• 3 classes– Myxini (hagfishes)
– Cephalaspidimorphi (lampreys)
– Pteraspidimorphi (extinct)
SUPERCLASS AGNATHA
Courtesy: tolweb.org
SUPERCLASS AGNATHAClass Myxini
Order Myxiniformes (hagfishes)
• most primitive vertebrates• marine only• no larval stage (yet found)• degenerate eyes – no lens or iris• cartilaginous skeleton• no lateral line• one semicircular canal• prominent barbels• no separate dorsal fin
SUPERCLASS AGNATHAClass Myxini
Order Myxiniformes (hagfishes)
• scavengers (NOT parasites)
SUPERCLASS AGNATHAClass Myxini
Order Myxiniformes (hagfishes)
• structurally but not functionally hermaphroditic (function as male OR female at a given time)• no osmoregulation: body fluids at same salinity as ocean• ~ 40 spp. today• economic importance - leather and food source in Asia
• developed vertebrae• no paired fins; dorsal fin(s)• well developed eyes• gill pouches• two semicircular canals; single nostril
SUPERCLASS AGNATHAClass Cephalaspidomorphi
Order Petromyzontiformes (lamprey)
• long larval stage (ammocoetes)• ~ 30 species - anadromous and freshwater
• parasitic forms: larvae metamorphose, reproduce as parasites• non-parasitic forms: skip feeding stage
• non-parasitic forms (detritus-feeders) develop from parasitic forms only in fresh water
SUPERCLASS AGNATHAClass Cephalaspidomorphi
Order Petromyzontiformes (lamprey)
• Economic importance– food source (Europe, Asia)– Great Lakes fisheries – medical research
SUPERCLASS AGNATHAClass Cephalaspidomorphi
Order Petromyzontiformes (lamprey)
SUPERCLASS AGNATHAClass Myxini
Order Myxiniformes (hagfishes)Class Cephalaspidomorphi
Order Petromyzontiformes (lamprey)
SUPERCLASS GNATHOSTOMATAClass Chondrichthyes Subclass Holocephali
Order Chimaeriformes (chimaeras) Subclass Elasmobranchii
9 orders (sharks, rays, skates)Class Sarcopterygii Subclass Coelacanthimorpha
Order Coelacanthiformes (coelacanths) Subclass Dipnoi
Order Ceratodontiformes (lungfish)Order Lepidosireniformes (S. American, African lungfish)
Class Actinopterygii - (rayfins, higher bony fishes) Subclass Chondrostei
Order Polypteriformes (birchirs, reedfish)Order Acipenseriformes (sturgeons, paddlefishes)
Subclass NeopterygiiOrder Semionotoformes (Lepisosteiformes) (gars)Order Amiiformes (bowfin)
Division Teleostei35-38 orders (modern body fishes)
• jawed
• gills are slits
• paired fins
• Silurian (400 MYA)
• 4 classes– Placodermi (extinct)
– Chondrichthyes
– Sarcopterygii
– Actinopterygii (rayfins, higher bony fishes)
SUPERCLASS GNATHOSTOMATA
• Extinct• jaws first appear• gill arches first appear• paired fins• bony plates
Courtesy: http://universe-review.ca
SUPERCLASS GNATHOSTOMATAClass Placodermi
• Chimaeras, sharks, skates & rays
– cartilaginous
– teeth not fused to jaws
– ‘placental’ to oviparous reproduction• embryos are sometimes encased
• gestation up to 2 yrs
Courtesy: http://www.chm.bris.ac.uk
Courtesy: http://www.jaxshells.org
SUPERCLASS GNATHOSTOMATAClass Chondrichthyes
SUPERCLASS AGNATHAClass Myxini
Order Myxiniformes (hagfishes)Class Cephalaspidomorphi
Order Petromyzontiformes (lamprey)
SUPERCLASS GNATHOSTOMATAClass Chondrichthyes Subclass Holocephali
Order Chimaeriformes (chimaeras) Subclass Elasmobranchii
9 orders (sharks, rays, skates)Class Sarcopterygii Subclass Coelacanthimorpha
Order Coelacanthiformes (coelacanths) Subclass Dipnoi
Order Ceratodontiformes (lungfish)Order Lepidosireniformes (S. American, African lungfish)
Class Actinopterygii - (rayfins, higher bony fishes) Subclass Chondrostei
Order Polypteriformes (birchirs, reedfish)Order Acipenseriformes (sturgeons, paddlefishes)
Subclass NeopterygiiOrder Semionotoformes (Lepisosteiformes) (gars)Order Amiiformes (bowfin)
Division Teleostei35-38 orders (modern body fishes)
SUPERCLASS GNATHOSTOMATAClass Chondrichthyes
Subclass Holocephali
Order Chimaeriformes (chimaeras)
• typically in shallow to mid-depthwater
• all marine• Cretaceous
ratfish
SUPERCLASS GNATHOSTOMATAClass Chondrichthyes
Subclass Holocephali
Order Chimaeriformes (chimaeras)
• gills in four pairs• spiracle absent• skin naked in adults• cloaca absent• males have pelvic intromittent organs (claspers)• two dorsal fins, first erectile with a spine and poison gland• diphycercal tail (symmetrical-tapering-whiplike)
SUPERCLASS GNATHOSTOMATAClass Chondrichthyes
Subclass Holocephali
Order Chimaeriformes (chimaeras)
elephantfish,plownose
• upper jaw/mouth fused to cranium• teeth are grinding plates