Ichthyology Final: Groups & their traits

Superclass Gnathostomata

jaws, paired fins, 3 semicircular canals, dentine based teeth

Subclass Holocephali

subclass under Class Chondrichthyes containing one order, includes chimaeras and ratfish

Subclass Euselachii

lateral gill openings, pectoral fins behind head, continually replaced tooth rows, hyostylic jaw

Superorder Squalomorphi

small, pelagic and benthic sharks, some with pointed or pavement teeth

Superorder Galeomorphi

large pelagic predators, blade like teeth

Division Batomorphi

ventral gills, enlarged pectoral fins, depressiform body shape, euhyostylic jaw

Class Osteichthyes

Subclass Sarcopterygii

lobe fins

Infraclass Dipmomorpha

Infraclass Actinistia

Subclass Actinopterygii

Infraclass Cladistia

Infraclass Chondrostei

Grade Neopterygii

Infraclass Holostei

Division Teleostomorpha

Subdivision Teleostei

ungraded division with cycloid or ctenoid scales, homocercal caudal fin, premaxilla moveable, branchiostegal rays

Cohort Elopomorpha

leptocephalus larvae, numerous branchiostegal rays (15+), teeth on the parasphenoid

Cohort Osteoglossomorpha

freshwater, most possess only the left ovary, epibranchial bones absent, supraorbital absent

Cohort Otocephala

cohort with otophysic connection between gas bladder and inner ear (in most)

Superorder Alepocephali

Superorder Ostariophysi

unique otophysic condition, has shreckstoff alarm substance, physostomous gas bladder, contains 70% of freshwater fish and 30% of all fish

Series Otophysi

weberian apparatus developed, tubercles in breeding males, pharyngeal teeth

Cohort Euteleostei

Order Lepidogalaxiiformes

neck joint, internal fertilisation, lack eye muscles

Order Salmoniformes

axillary process, adipose fin, last 3 vertebrae upturned

Superorder Protacanthopterygii

Order Esociformes

sagittiform body, toothless maxilla included in gape

Superorder Osmeromorpha

Order Argentiniformes

crumenal organ, adipose fin, marine, many bathypelagic

Order Galaxiiformes

no scales but have lateral line, no keel, no cucumber scent, live in southern hemisphere

Order Osmeriformes

cucumber scent, articular absent/reduced, spawn in freshwater, adipose fin usually present

Order Stomiiformes

photophores, large mouth with teeth on premaxilla and maxilla, rete mirabile posterior gas bladder, genus Cyclothone is one of most abundant vertebrates

Superorder Scopelomorpha

adipose fin supported by cartilaginous plate, perform DVM,

Superorder Lamprimorpha

Superorder Paracanthopterygii

Order Myctophiformes

adipose fin supported by cartilaginous plate, commonly perform DVM, upper pharyngeal jaw dominated by third pharyngobranchial

Order Lampriformes

maxilla slides with premaxilla, unique protrusible jaw, lack true spines

Order Percopsiformes

freshwater fish in eastern USA, premaxilla is nonprotrusible, ctenoid scales

Order Stylephoriformes

marine abyssal fish, ribbonlike body, 40-fold enlargement of mouth

Order Gadiformes

isocercal caudal fin, 2-3 dorsals, pelvic thoracic or jugular, lack spines, mostly marine

Superorder Acanthopterygii

long ascending premaxillary process, Baudelot’s ligament originating on basioccipital of skull, upper pharyngeal jaw supported by second and third epibranchial bones

Series Percomorpha

Order Ophidiiformes

eel like with tapering body, pelvic fins jugular or on chin if present, some parasitic or commensal, deep sea fish

Order Batrachoidiformes

3 pairs of gills, multiple lateral lines, fastest contracting muscles, larvae with enormous yolk sacs

Order Gobiformes

pelvic fins usually united forming round disc, gas bladder absent, parietal bones absent, many with terrestrial-like adaptations

Order Mugiliformes

two widely separated dorsal fins, pelvic fins subabdominal, small triangular mouth, gizzard like stomach

Order Cichliformes

single nostril on each side, lateral line is interrupted, mostly freshwater, largest & fastest vertebrate adaptive radiation

Order Atheriniformes

many have 2 dorsal fins with the first having flexible spines, usually abdominal pectoral fins, most diverse freshwater group in Australia

Order Beloniformes

lack spines, nonprotrusible upper jaw, lower caudal lobe has more rays than upper (hypocercal tail)

Order Cyprinodontiformes

symmetrical caudal fin supported internally by a single bone, first rib attached to second vertebra, single dorsal fin

Order Pleuronectiformes

most asymmetric vertebrate, highly compressed body, ontogeny characterized by migration of one eye, anteriorly placed dorsal fin, minimally overlapping neurocranium

Order Perciformes

most diversified of all fish groups, mostly marine

Order Scorpaeniformes

suborbital stay/mail-cheeked, head and body tend to be spiny or have bony plates, backwardly directed opercular spine, venomous spines

Order Lophiiformes

1st dorsal ray transformed into illicium and esca, small gill opening behind pectoral fin base, pelvic fins in front of pectoral fins, no ribs, first vertebra fused to skull

Order Tetraodontiformes

reduced and fused bones: 21 or fewer vertebrae, lack nasals, lack parietals, lack infraorbital bones, hyomandibular and palatine fused to skull, premaxilla and maxilla fused, gill openings restricted, scales modified as spines, shields, or plates

Order Chimaeriformes

single opercular flap, one tooth plate in lower jaw, 2 pairs in upper jaw, has a tentaculum covered in hooks

Order Pristiophoriformes

long saw-shaped snout, unequal sized teeth, barbels

Order Hexanchiformes

6-7 gill slits, anal fin, 1 dorsal fin

Order Squaliformes

no anal fins, 2 dorsal fins

Order Squatiniformes

depressiform body shape, large pectoral fins, terminal mouth

Order Echinorhiniformes

Order Carchariniformes

nictitating membrane, large mouth, lack spiracles

Order Lamniformes

large mouth, no nictitating membrane in eye, broad gill slits

Order Orectolobiformes

mouth in front of eyes, naso-oral grooves and barbels

Order Heterodontiformes

2 dorsal fins with spines, crest above eye

Order Rhinopristiformes

body between shark and skate, 2 dorsal fins, caudal fin well developed, lecithotropic vivarity

Order Rajiformes

tail slender without stinging spines, thorns or prickles on dorsal midlines, tail usually with two small dorsal fins near its tip

Order Torpediniformes

electric organ on pectorals, soft and loose skin, rounded disc

Order Myliobatiformes

whiplike tail with stinging serrated spine, tail usually without dorsal fins

Order Coelacanthiformes

tri-lobed diphycercal tail, fat-filled gas bladder, has the largest ova of any fish and the longest gestation time of any bony fish

Order Ceratodontiformes

order with functional lungs, autostylic jaw, absent premaxilla and maxilla

Order Polypteriformes

order with lobed pectoral fins, lungs, dorsal finlets, and ganoid scales

Order Acipenseriformes

order with cartilaginous skeleton, heterocercal tail, spiral valve intestine, endocranium with extensive rostrum

Class Chondrichthyes

cartilaginous, ceratotrichia, placoid scales, males with claspers, rectal gland excretes salts

Infraclass Elasmobranchii

5-7 gill openings, jaw not fused to neurocranium, spiracles usually present

Order Lepisosteiformes

opisthocoelous vertebrae, ganoid scales, abbreviated heterocercal tail

Order Amiiformes

abbreviated heterocercal tail, large median gular plate, ocellus in males

Order Elopiformes

gular plate, 25-35 branchiostegal rays, highly fecund, leptocephalus larvae with forked tail

Order Albuliformes

gular plate, 6-15 branchiostegal rays, inferior mouth

Order Notacanthiformes

large leptocephalus larvae (2m), long anal fin with numerous spines

Order Anguilliformes

anguillliform body shape and swimming pattern, pelvic girdle and pelvic fins absent, narrow gill openings, lack gill rakers, scales usually absent

Order Hiodontiformes

freshwater found in North America, nasal bones are tubular and highly curved, opercle with recurved process

Order Osteoglossiformes

glossohyal plate bites against parasphenoid, premaxilla is fixed to the skull

Order Clupeiformes

gas bladder is connected to ear by bullae, keel-like bellies made of scutes, most are plankton feeders, most abundant fish in the world

Order Alepocephaliformes

crumenal organ, last 2 rakers interdigitate, dorsal fin well posterior, no adipose fin or gas bladder despite being in Otocephala

Order Gonorynchiformes

primitive weberian apparatus, suprabranchial organ

Order Cypriniformes

freshwater, lack teeth on oral jaw, protrusible upper jaw, kinethmoid bone, no adipose fin, absent in Australia and South America, largest order of fish

Order Characiformes

adipose fin, nonprotrusible upper jaw, jaw teeth present, body scaled, freshwater and found in Africa and Americas

Order Siluriformes

adipose fin, barbels, no scales, spine-like rays, fusion of skull bones, intermuscular bones absent

Order Gymnotiformes

electrolocation, no dorsal or pelvic fins, long undulatory anal fin

Neoteleostei

unranked grouping, retractor dorsalis muscle (upper pharyngeal teeth can be pulled back) and tripartite occipital condyle (first vertebra moves with 3 bones of skull)

Superorder Acanthomorpha

spiny ray finned fishes, most members have true spines in dorsal, anal and pelvic fins, 60% of known teleosts and 1/3 of vertebrate species