| SYSTEMATIC BIOLOGY |
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| CLASS OSTEICHTHYES |
Osteichthyes (o-sti-IK-thes) is made of two Greek roots that mean "bony fish" [bony -osteinos (οστέινος); and fish -ichthys (ιχθύς)]. This is a reference to the presence of bone in the skeleton rather than cartilage of most members of this group.
The Osteichthyes is the most speciose class of the Craniata, and comprises nearly 50% of all known vertebrates. Such diversity defies a simple description; however, the osteichthyes tend to have the following characters: gills covered by an operculum, one or more dorsal fins, usually one anal fin, most have a homocercal tail and a body covered with scales, usually overlapping. The class is formed of two unequal clades (presented here as subclasses) defined by the structure of their paired fins: Actinopterigii (the ray-finned fishes) and the Sarcopterygii (the lobe-finned fishes).
Benton (2005) describes three successive radiation events for the actinopteryrgian bony fishes:
Basal actinopterygian or ‘chondrostean’ radiation: Carboniferous – Triassic
Basal neopterygian or ‘holostean’ radiation: Triassic – Jurassic
Teleost radiation: Jurassic – present
Remnants of the chondrostean radiation are represented today by two genera of Cladistia (bichirs) and six genera of Chondrostei (sturgeons and paddlefish). The living cladistans are restricted to lakes and rivers of central Africa and characterized by having lungs, lobe-like paired fins, ganoid scales, a square body (in cross-section), and in-line fins punctuated by a series of spines. Thus, they look like snakes with a spiny dorsal fin. Their pectoral fins are strong and can be used to propel themselves over land.
The Chondrostei [a name derived from the Greek word for cartilage -chrondros (χόνδρος)] is so-called because their skeleton is poorly ossified. Though once quite diverse, the Chondrostei now are represented by sturgeons and paddlefish, both mainly freshwater taxa of large rivers and lakes in the northern hemisphere. Sturgeons have scales reduced to a few bony plates in a row down their sides. They have a characteristic long rostrum and subterminal mouth. The gigantic beluga sturgeon (Huso), the source of black caviar, and most other sturgeon species experienced dramatic reductions through the 20th Century due to pollution, dams, and over fishing. Paddlefish have a large paddle-like extension of the rostrum and a large mouth/pharynx with which they draw in water and capture plankton.
The holostean radiation of the Triassic through the Jurassic produced a great diversity of fishes with nearly symmetrical, but still heterocercal, tails. Those alive today are represented by three genera, 2 gars and 1 bowfin. Both the gars and bowfins live in freshwater and both are powerful predators. The gars typically have bodies that are round in cross-section and have elongate jaws filled with needle-like teeth. Bowfins have a more rounded head but teeth line the jaws and palate. In addition, they have a distinctive long dorsal fin. The Bowfin (Amia) is the closest living species to the modern fishes, the teleosts.
The teleost radiation began in the Jurassic and continues today. This group of bony fishes is by far the the most diverse of all the fishes, indeed of all the craniates. The teleosts are characterized by having true homocercal tails and a moveable premaxilla. According to Lundberg (2006) the extant teleosts are represented by members of two basal groups, the Elopomorpha (eels, tarpons, etc.), and Osteoglossomorpha (the bonytongues) together with a monophyletic line of the other teleosts. The Otocephala (Herrings and Carp) are the sisters to the Euteleostei (most of the bony fishes including Salmon, Pike, and Perch), the crown teleost taxa.
The Elopomorpha (eels, tarpons and their relatives) are characterized by having a larval form, the leptocephalus, that is long and ribbon-like. Usually, the larvae grow to be longer than the adult that the metamorphose into. The most notable members of this group are the eels, which, as adults, have a continuous in-line fin that from the mid dorsal to the mid ventral. The North American and European freshwater eels (sibling species in the genus Anguilla) migrate to the Sargasso Sea where they spawn. The leptocephali return to the respective estuaries, metamorphose into a juvenal form called an elver.
Osteoglossomorpha (bonytongues) have tongue bones that usually possess teeth. Thus, they can tear prey with their jaws and tongues. Most are long and thin and exhibit some form of parental care. The Old World knifefishes and elephantfishes orient and find prey by generating a weak electromagnetic field.
Herrings and Carp (Otocephala) have a series of small bones that connect the ear and the air bladder, which provides a means to detect sound vibrations and transfer them to the inner ear. Thus, very different fish like herrings (sardines, anchovies, and menhadens) are united with carp (including suckers and goldfish) and the catfishes. Herrings are very important members of the open water fish community in the oceans where they feed on plankton. They are the base of several important global fisheries like the anchovy catch off the coast of Chile. Carps, suckers, and catfishes, though present in marine environments, are very common in freshwater. Some of the catfishes in the new world have developed electric field generating organs independently of the old world knifefishes (parallel evolution).
The Euteleostei is divided into the Procanthopterygii (salmon and pike) and the Neoteleostii (the most speciose and diverse group of bony fishes). The salmonids (salmons and trout) are powerful predatory fish that are the basis of important sport and commercial fisheries. Many salmon species are anadromous and spawn in freshwater but their young move to the marine environment where they mature and return to freshwater after years in the open ocean. Pike are ambush predators with a elongate jaws and a body shape that is reminiscent of the gar in which the dorsal and anal fins serve as extensions of the caudal fins.
The Neoteleostii are extraordinarily diverse and vary in form from the common yellow perch and smallmouth bass to the gigantic mola, a fish that can grow to 3 meters and weigh more than a metric ton. Most fish in this group have both sets of paired fins (pectoral and pelvic) very close together and joined by a bony connection. Some like the tuna are capable of limited endothermy, grow to 4 meters and can swim at high speed for extended periods of time. Others like the flatfishes undergo a kind of metamorphosis in which their eyes move to one side of their heads and they lie mostly buried in the substrate where they hide from predators and ambush prey.
The other major type of bony fish is the Sarcopterygii or lobe-finned fishes. Rather that having fins of bony rays, they have fins with fleshy lobes from which rays emerge. Of particular interest is the bony architecture of the lobe, which, in the case of the paired fins, has bones that are homologous to those of tetrapod limbs. Nelson (2007) considers the Sarcopterygii to be a separate class and to include the lungfishes, coelocanths, and all tetrapods. His taxonomy is a strict application of cladistic rules. In fact, a coelocanth or lungfish is more closely related to a rat than it is to a perch. Nevertheless, in this taxonomy, we consider the lobe-finned fishes to be sisters to the tetrapods. The extant lobe-fins are reduced to two species of coelocanth (a deep sea fish in the Indian Ocean with a characteristic diphycercal tail with a central lobed tuft), and the lungfishes, which have a few representatives on Australia, South America, and Africa.
| HIERARCHICAL TAXONOMY OF THE CLASS OSTEICHTHYES. The following descriptions come from Benton (2005) and Nelson (2006). The structure of the following system is also based, in part, on the phylogenetic treatment by Mikko's Phylogeny Web (from the Finnish Museum of Natural History). Taxa in red are extinct. |
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(Left) a ray-finned fish from the Australian Barrier Reef (Image from the Systematic Biology Diversity Archive). (Right) Latimeria, a lobe-finned fish from the Indian Ocean. Image from: http://www.uni-heidelberg.de/presse/news/latimeria_vv.jpg CLASS OSTEICHTHYES The bony fishes generally have paired pectoral and pelvic fins with two main clades: the ray-finned fishes (Actinopterygii) and the lobed finned fishes (Sarcopterygii). The bony fishes appeared in the late Silurian and survive to the present where they are the dominant aquatic vertebrates. MAJOR GROUPS OF EXTANT OSTEICHTHYES ACTINOPTERYGII (RAY-FINNED FISHES) CLADISTIA (POLYPTERUS) CHONDROSTEI (STURGEONS AND PADDLEFISHES) NEOPTERYGII (GARS , AMIAFORMES+ MODERN BONY FISHES)
SARCOPTERYGII (LOBE-FINNED FISHES)
INCERTAE SEDIS: PSAROLEPIS+ Psarolepis shows characters consistent with both the ray-finned and lobe-finned fishes. (Upper Silurian and lower Devonian). See Zhu et al. (1999), Zhu and Schultze (2001). The ray-finned fishes. ORDER CHEIROLEPIDIFORMES+ FAMILY CHEIROLEPIDIDAE Slender and long with heterocercal tail. Scales of bone, dentine and enamel are interlocking. Leading edge of tail covered by larger scales. Teeth on maxilla, premaxilla, and dentary bones. Fast swimmer, powerful predator. (~25cm). Middle Devonian FAMILY CHEIROLEPIDAE Cheirolepis. ORDER CLADISTIA (Nelson, 2006, treats this as a subclass) Ganoid scales, body round in x-section. Tail rounded. FAMILY GILDAYICHTHYIDAE+ Small, eel-like. Middle Carboniferous Paratarassius. FAMILY POLYPTERIDAE Called the bichir, it has a row of spine-supported fins down the back. Freshwater from rivers and lakes in central Africa. Middle Cretaceous to present Polypterus,
Erpetoichthys; Dagatella+, Latinopollis+, Pollia+,
Sainthilairia+, Serenoichthys+. ORDER
ACTINOPTERI+ Likely
paraphyletic group of families. FAMILY
MIMIIDAE Mimia FAMILY
STEGOTRACHELIDAE Upper
Devonian Moythomasia. FAMILY
PTYCHOLEPIDIDAE Triassic
to Lower Jurassic Ptycholepis. FAMILY
AMBLYPTERIDAE Carboniferous
to Permian ORDER
PALAEONISCIFORMES+ Additional
supraorbitals and a keystone-shaped dermosphenotic; eyes large and far forward;
tail heterocercal (dorsal lobe becoming less reduced in later forms). Mississippian
to lower Jurassic. Unassigned
Genus: Coccolepis. SUBORDER
PALEONISCOIDEI Heterogeneous
group of primitive palaeoniscids. Devonian. FAMILY
AEDUELLIDAE FAMILY
ACROLEPIDAE Acrolepis,
Boreosomus, Pteronisculus. FAMILY
AMBLYPTERIDAE Amblypterus,
Paramblypterus. FAMILY
BIRGERIIDAE Fish
very large; massive jaws and teeth. Triassic
to lower Jurassic. Birgeria,
Canobius. FAMILY
COMMENTRYIDAE FAMILY
ELONCHTHYIDAE FAMILY
PALEONISCIDAE FAMILY
PYGOPTERIDAE FAMILY
RHABDOLEPIDAE Osorioichthys. FAMILY
RHADINICHTHYIDAE FAMILY
AESOPICHTHYIDAE FAMILY
STEGOTRACHELIDAE Stegotrachelus,
Tegeolepis. SUBORDER
REDFIELDOIDEI Bodies
fusiform; mouth terminal or subterminal; dorsal and anal fins far back and
opposite each other; reduced branchiostegal rays.
Triassic
to lower Jurassic; freshwater FAMILY
REDFIELDIIDAE Characteristically
modified snout and orbit; common in Triassic freshwater lake deposits. Redfieldius,
Brookvalia, Dictyopyge, Helichthys, Schizurichthys. SUBORDER
PLATYSOMOIDEI Body
deep and compressed. Mississippian
to lower Triassic. (Marine and freshwater) FAMILY
BONASTRANIIDAE FAMILY
CHIRODONTIDAE FAMILY
PLATYSOMIDAE SUBORDER
DORYPTEROIDEI Body
deep and without scales; pelvic fin in front of pectorals; caudal peduncle
narrow. Carboniferous
to upper Permian. FAMILY
DORYPTERIDAE Similar
to the amphycentrids. Permian Dorypterus. FAMILY
AMPHICENTRIDAE Deep
bodied laterally compressed fishes. Dorsal and anal fins long; mouth modified
into a beak with crushing teeth. Carboniferous. Amphicentrum. ORDER
TARRASIIFORMES+ Dorsal
and anal fins continuous with the diphycercal tail; no pelvic fins; scales
reduced or absent; body elongate; pectoral fins with fleshy lobes. Mississippian FAMILY
TARRASIIDAE ORDER
GUILDAYICHTHYIFORMES+ Body
very compressed and discoid; ganoid scales with peg and socket joints. Mississippian
(Marine) FAMILY
GUILDAYICHTHYIDAE Guildayichthys,
Discoserra. ORDER
PHANERORHYNCHIFORMES+ Body
very much like sturgeon. Pennsylvanian. Phanaerorhynchus. Sturgeons. Caudal fin heterocercal; skeleton cartilaginous; intestine with spiral valve. SUBORDER
UNNAMED+ Upper
Jurassic. FAMILY
PEIPIAOSTEIDAE Peipiaosteus,
Stichopterus, Spherosteus, Yanosteus. SUBORDER
CHONDROSTEOIDEI+ Mouth
subterminal Jurassic
( FAMILY
CHONDROSTEIDAE Chondrosteus,
Strongylosteus, Gyrosteus. SUBORDER ACIPENSEROIDEI No opercule (cover made of sub opercule); long rostrum. Sturgeons are large fish of the northern hemisphere. The skeleton is poorly ossified and the scales are reduced to a single row of bony plates down each side. Anadromous and freshwater. Upper Cretaceous to present FAMILY ACIPENSERIDAE Acipenser,
Huso, Pseudoscaphirhynchus, Scaphirhynchus, Protoscaphirhynchus+. FAMILY POLYODONTIDAE Paddlefish
are large riverine fishes with a large paddle-like extensions of the rostrum.
Poorly ossified skeleton. They
feed by filtering plankton. Extant species in Lower Cretaceous to present. Polyodon,
Psephurus, Protopsephurus+, Paleopsephurus+, Crossopholis+. ORDER
PTYCHOLEPIFORMES+ Triassic
to Jurassic. ( ORDER
SAURICHTHYIFORMES+ Fish
body long (up to 1 m) very similar to pike and likely an ambush predator, too. Triassic
to Jurassic. FAMILY
SAURICHTHYIDAE Saurichthyes,
Acidorhynchus. ORDER
PHOLIDOPLEURIFORMES+ Fishes
slender with large rectangular scales on the sides.
Middle
Triassic. FAMILY
PHOLIDOPLEURIDAE Pholidopleurus,
Australosomus. ORDER
PERLEIDIFORMES+ Tail
fin rays nearly equal above and below. Nelson
(2006) refers to this as an artificial collection of families. Triassic
to lower Jurassic Perleidus, Cleithrolepis, Aetheodontus,
Dipteronotus, Meridensia, Peltopterus, Habroichthys, Thoracopterus. Families
include: FAMILY
CEPHALOXENIDAE FAMILY
COLOBODONTIDAE FAMILY
PLATYSIAGIDAE FAMILY
PELTOPLEURIDAE FAMILY
CLEITHROLEPIDAE FAMILY
PERLEIDIDAE ORDER
LUGANOIIFORMES Triassic. Luganoia. ORDER LEPIDOSTEIFORMES (GIMGLYMODI?) FAMILY LEPISOSTEIDAE Gars. Freshwater; eastern Cretaceous to the present. Lepisosteus, Atractosteus, Masillosteus+,
Obaichthys+, Oniichthys+. ORDER
SEMIONOTIFORMES+ FAMILY
SEMIONOTIDAE (LEPIDOTIDAE) Fishes
small; symmetrical tails; large dorsal and ventral fins short; jaws project well
forward. Upper
Triassic to Cretaceous. Semionotus, Lepidotes, Paralepidotus,
Acentrophorus. FAMILY
DAPEDIDAE Similar
to the semiontids; they are deep-bodied with long anal and dorsal fins. Upper
Triassic to lower Jurassic (Marine and freshwater deposits of Dapedium. ORDER
MACROSEMIIFORMES+ FAMILY
MACROSEMIIDAE Small
fishes with a high dorsal fin. They have unusual bones around the eye. Triassic
to lower Cretaceous ( Macrosemius. THE
HALECOSTOMI –clade that includes the
Halicomorphi and the Teleostei. Nelson
(2006) treats this as an order within the Neopterygii. ORDER
PYCNODONTIFORMES+ Incertae Sedis according to Nelson (2006). Placed in the Halicostomi by Poyato-Ariza and Wenz (2002). Deep
bodied fish with long dorsal and anal fins and a true homocercal tail. An
elongate snout with crushing teeth. Triassic
to Eocene. Reefs and lagoons of the SUBORDER
UNNAMED Primitive
pycnodontiform fishes. FAMILY
UNNAMED Paramesturus. FAMILY
GYRODONTIDAE Central
papilla on vomerine and prearticular teeth; sagittal flanges on neural and
haemal spines. Gyrodus. FAMILY
MESTURIDAE Primitive
family; maxilla ornamented and elongate; ridges on vomerine and prearticular
teeth; first dorsal ridge scale larger than other dorsal ridge scales. Mesturus,
Micropicnodon. FAMILY
UNNAMED Arduafrons. FAMILY
BREMBODONTIDAE Three
premaxillary teeth; eight or nine teeth on the vomer; fringing fulcra onpaired
and unpaired fins; 10-14 dorsal ridge scales; 6 or fewer postcloacal ventral
keel scales. Brembodus,
Gibbodon (Nelson, 2006, separates this
genus into its own family, Gibbodontidae). SUBORDER
PYCNODONTOIDEI Opercular
process of the hyomandibular absent; crenulations on vomerine and prearticular
teeth weak or absent.; scales not covering whole body and absent between the
bases of the unpaired fins. FAMILY
UNNAMED Eomesodon,
Apomesodon. FAMILY
COCCODONTIDAE Six
to eight epichordal elements in the tail; hypochordal elements enlarged in the
tail; first dorsal ridge scale larger than the subsequent scales; three or fewer
ventral keel scales. Coccodus,
Trewavasia, Ichthyoceros. FAMILY
PYCNODONTIDAE Have
a parietal peniculus-like structure, no suborbitals, cheeks naked, maxilla
edentulous, 2-3 dentary teeth, scales weakly ossified; spines on ventral keel
scales touching. Macromesodon,
Stenamara, Stemmatodus, Anomoeodus, Ocloedus, Tepexichthys. Porscinites,
Iemanja, Coelodus. Pycnodus,
Oropycnodus. Nursallia,
Abdobalistum, Paleobalistum. Poyato-Ariza
and Wenz (2002) do not consider the following taxa to be members of this order.
Presently, they occupy a position of Incertae
Sedis. FAMILY HADRODONTIDAE Hadrodus. ORDER HALECOMORPHI (AMIIFORMES) Bowfins. These fish have a special jaw joint formed by an additional element called the symplectic. Usually freshwater. FAMILY AMIIDAE Amia, Amiopsis+, Calamopleurus+, Cyclurus+, Solnhofenamia+, Vidalamia+. FAMILY PARASEMIODONTIDAE+ Small fish with large eyes and a jaw like the neopterigyians. Usually marine. Triassic. Parasemionotus, Watsonulus. THE TELEOSTEI – Diverse clade of fishes that have homocercal tails. The vertebrae do not run into the upper lobe of the tail. Teleosts also have a moveable premaxilla. THE
BASAL TELEOST GROUPS ORDER
PACHYCORMIFORMES + Nelson
(2006) excludes this group from the teleosts.
Here it is considered to be one of the basal groups FAMILY
PACHYCORMIDAE Most
well known members were very large, scaleless filter-feeders, much like the
paddlefish of today. Likewise, it
had a large filtering basket made from modified gill components. No pelvic fins. Jurassic
to upper Cretaceous Leedsichthyes,
Asthenocormus, Euthynotus, Hypsocormus, Orthocormus, Pachycormus, Prosauropsis,
Protosphyraena. ORDER
ASPIDORHYNCHOFORMES+ Position
is uncertain in the system of Nelson (2006) in which it does not occupy a
position within the Teleostei; howeverBrito (1999) presents compelling evidence
that the tail skeleton is that of a teleost. FAMILY
ASPIDORHYNCHIDAE Round
bodied fishes with upper part of the skull extended into a long pointed snout;
interoperculum absent; dorsal and anal fins opposite each other. Mostly marine;
up to 1m. Upper
Jurassic to Cretaceous Aspidorhynchus,
Belonostomus, Vinctifer. ORDER
PHOLIDOPHORIFORMES+ FAMILY
PHOLIDOPHORIDAE Generally
small hunting fishes. Besides the
premaxilla, the had a dermethmoid as an additional tooth-bearing bone. Upper
Triassic to lower Triassic Eurycormus. The
order has four other families according to Nelson (2006): Archaeomaenidae,
Ichthyokentemidae, Oligopleuridae, Pleuropholidae. ORDER
LEPTOLEPIDOFORMES+ FAMILY
LEPTOLEPIDIDAE Small
fish with cycloid scales. Their
vertebrae were fully ossified. Likely
marine. Triassic
to Cretaceous Varasichthyes. ORDER
TSELFATIIFORMES+ This
group occupies an uncertain position; Fish with deep bodies; dorsal fin along
most of the back; pectoral fins high on the body; pelvic fins absent or reduced;
caudal fin deeply forked; palate toothed. Cretaceous. FAMILY
PLETHODIDAE Plethodus. FAMILY
PROTOBRAMIDAE Abisaadichthys,
Eusebichthys, Protobrama. FAMILY
TSELFATIIDAE Tselfatia. ORDER
ICHTHYODECTIFORMES+ Nelson
(2006) considers this group to be basal in the Osteoglossomorpha.
Anal fin long and opposite the dorsal fin.
Most were marine and predators. At
least one genus grew to 4m long. Middle
Jurassic to upper Cretaceous. FAMILY
ALLOTHRISSOPIDAE Upper
Jurassic to upper Cretaceous Allothrissops,
Pachythrissops, Tharsis, Eubiodectes, Thrissops. FAMILY
OCCITHRISSOPIDAE Middle
Jurassic Occithrissops. FAMILY
CLADOCYCLIDAE Cretaceous. Cladocyclus,
Chiromystus, Cladocyclus, Chirocentrites. FAMILY
SAURODONTIDAE Cretaceous. Saurodon,
Saurocephalus. FAMILY
ICHTHYODECTIDAE Very
large predators (>4m long) Cretaceous Gillicus,
Ichthyodectus, Xiphactinus. OSTEOGLOSSOMORPHA
–BONY-TONGUED TELEOSTS Most of these taxa exhibit some type of parental care for the young. ORDER
LYCOPTERIFORMES+ Considered
sister to all extant Osteoglossomorpha. Upper
Jurassic to Lower Cretaceous. FAMILY
LYCOPTERIDAE Lycoptera. ORDER HIODONTIFORMES Mooneyes. This group was recently
separated from the Osteoglossiformes (Hilton 2003).
Freshwater; Eocene to present. FAMILY HIODONTIDAE Anal fin long and not joining the tail; distinct pelvic fins. Up to 0.5m long. Hiodon,
Eohiodon+. ORDER OSTEOGLOSSIFORMES Southern Hemispheric distribution. Small fish of fresh water. They bite using teeth on a bony tongue and elements on the roof of the mouth. Upper Jurassic to present FAMILY OSTEOGLOSSIDAE Bonytongues.
Carnivores or omnivores of freshwater. Circumtropical;
Eocene to present. Osteoglossum,
Scleropages,Pantodon, Arapaima, Heterotis, Phareodus+,
Brychaetus+. FAMILY PANTODONTIDAE Butterflyfishes FAMILY NOTOPTERIDAE Featherfin
Knifefishes or Chilata,
Notopterus, Papyrocranus, Xenomystus. FAMILY MORMYRIDAE Elephantfishes.
Freshwater; tropical Mormyrus,
Brienomyrus, Campylomormyus, Gnathonemus, Hippopotamyrus, Hyperopsis,
Marcusenius, Mormyrops, Petrocephalus, Pollimyrus, Stomatorhinus. FAMILY GYMNARCHIDAE Gymnarchus. FAMILY
ARARIPICHTHYIDAE+ Body
deep; dorsal and anal fins long; pelvic fins absent; pectoral fins attached low
on body; caudal fin forked. Lower
Cretaceous of Araripichthys. ELOPOMORPHA – EELS, TARPONS, & BONEFISH Fish in this
group produce larval forms that are ribbon-like (leptocephalus larva). ORDER ANGUILLIFORMES (APODES) Though quite variable in form, all members of this group have a distinctive leaf-like larva. Eels exhibit extreme modification of their bodies which includes loss of caudal fins, loss of ribs, loss of and fusion of many skull elements in addition to extreme elongation of the body. 15 families. Lower Cretaceous to present SUBORDER ANGUILOIDEI Frontals sutured. FAMILY ANGUILLIDAE Freshwater Eels. Catadromous; tropical and temperate seas. Minute scales; pectoral fins well developed. FAMILY HETERENCHELYIDAE Mud Eels. Marine; tropical Atlantic (Mediterranian) and eastern Pacific. No pectoral fins; no scales; mouth large; dorsal fin begins over gills; animals burrow (head first). Panturichthys,
Pythonichthys. FAMILY MORINGUIDAE Spaghetti Eels. Marine; rarely freshwater; tropical; Indian, Pacific, and western Atlantic oceans. Body very elongate; no scales; dorsal and anal fins reduced to folds; pectoral fin very reduced; eyes small and covered with skin; animals burrow head first. Moringua,
Neoconger. SUBORDER MURAENOIDEI Frontals sutured; no scales; eyes not reduced. FAMILY CHLOPSIDAE (XENOCONGRIDAE) False Moray Eels. Marine; tropical and subtropical; Atlantic, Indian, and Pacific oceans. Gill openings reduced to small round holes; pectoral fins absent or reduced. Boehlkenchelys,
Catesbya, Chilorhinus, Chilopsis, Kaupichthys, Powellichthys, Robinsia,
Xenoconger. FAMILY MYROCONGRIDAE Myroconger
Eels. Marine; eastern tropical Myroconger. FAMILY MURAENIDAE (HETEROMYRIDAE) Moray Eels. Marine; tropical and temperate seas. Gill openings restricted; no pectoral fins; long fang-like teeth. Gymnothorax,
Sphyraena, Caranax, Mycertoperca, Lutjanus. Anarchias,
Channomuraena, Scuticaria, Uropterygius. Echidna,
Enchelycore, Enchelynassa, Gymnomuraena, Gymnothorax, Monopenchelys, Muraena,
Rhinomuraena, Siderea, Strophidon, Thyrsoidea. SUBORDER CONGROIDEI Frontals fused; scales present in
a few members of one of the nine families. FAMILY SYNAPHOBRANCHIDAE Cutthroat
Eels. Marine; Arrowtooth Eels or Mustard Eels: Atractodenchelys, Dysommina, Ilyophis, Linkenchelys, Meadia, Thermobiotes. Cutthroat Eels: Haptenchelys, Synaphobranchus. Snubnose Parasitic Eel: Simenchelys. FAMILY OPHICHTHIDAE Snake Eels and Worm Eels. Marine (rarely freshwater); tongue not free; stiffened tail used to burrow tail-first (they move through the sediment both head and tail first); some very sharp-tailed. Worm Eels: Benthenchelys, Ahlia, Asarcenchelys, Glenoglossa, Mixomyrophis, Muraenichthys, Myrophis, Neenchelys, Pseudomyrophis, Schismorhynchus, Schultzidia. Snake Eels: Apterichtus,
Bascanichthys, Caecula, Callechelys, Cirrhimuraena, Dalophis, Echelus, Echiophis,
Ethadophis, Lamnostoma, Letharchus, Myrichthys, Mystriophis, Ophichthus,
Phaenomonas, Pisodonophis, Yirrkala. FAMILY COLOCONGRIDAE Shorttail Eels. Marine; Atlantic, Indian, and western Pacific oceans. Body short and stubby, short ssnout; pectoral fins present; vomerine teeth absent. Coloconger. FAMILY DERICHTHYIDAE Longneck
Eels. Marine; Derichthys,
Nessorhamphus. FAMILY MURAENESOCIDAE Pike Congers. Marine; tropical; Atlantic, Indian, and Pacific oceans. Teeth well developed, vomerine teeth present; pectoral fins well developed; eyes large and covered with skin; dorsal fin originates over or before pectorals. Congresox,
Cynoponticus, Muraenesox, Sauromuraenesox. FAMILY NEMICHTHYIDAE Snipe Eels.
Marine; Avocettina,
Labichthys, Nemichthys. FAMILY CONGRIDAE Conger Eels. Marine; tropical to temperate; Atlantic, Indian, and Pacific oceans. Pectoral fins present. This is a large, diverse family with three subfamilies, each described below. Heterocongrinae (Garden Eels): Pectoral fins reduced or absent; body very long and slender; mouth short with longer lower jaw; they hover straight up above their burrows, which in a colony looks like a garden of eels. Gorgasia,
Heteroconger. Bathymyrinae: Dorsal and anal fin rays unsegmented; pectoral fin well developed. Ariosoma,
Bathymyrus, Chiloconger, Parabathymyrus, Paraconger. Congrinae: Dorsal and anal fins developed; pectoral fins well developed. Acromycter,
Conger, Gavialiceps, Gnathophis, Hildebrandia, Lumiconger, Macrocephenchelys,
Rhechias, Rhynchoconger, Uroconger, Xenomystax. FAMILY NETTASTOMIDAE Duckbill
Eels. Marine; Facciolella,
Hoplunnis, Nettastoma, Nettenchelys, Saurenchelys, Venefica. FAMILY SERRIVOMERIDAE Sawtooth Eels. Marine; tropical to temperate; Atlantic, Indian, and Pacific oceans. Jaws very elongate, slender; vomerine teeth; usually black with silver sides. Serrivomer,
Stemonidium. ORDER SACCOPHARYNGIFORMES Sackpharynx Fishes. Highly derived fishes that lack the symplectic, opercular, branchiostegal rays, scales, pelvic fins, Pelvic fins, ribs, pyloric caeca, and swim bladder; caudal fin absent in most; anal fins long, and jaws elongate. SUBORDER CYEMATOIDEI FAMILY CYEMATIDAE Bobtail
Snipe Eels. Marine (bathypelagic); Cyema,
Neocyema. FAMILY SACCOPHYRINGIDAE Swallowers.
Marine; Saccopharynx. FAMILY EURYPHRYNGIDAE Gulpers or Pelican Eels. Marine; tropical, temperate; Atlantic, Indian, and Pacific oceans. Only teleost with 5 gill arches and 6 visceral clefts; mouth very large; mouths with minute teeth; pectoral fins highly reduced. Maximum length 75cm. Eurypharynx. FAMILY MONOGNATHIDAE Onejaw Gulpers. Marine; deep sea (>2,000m); Atlantic and Pacific. No upper jaw or pectoral fins; dorsal and anal fins without skeletal elements; rostral fang withglands. Maximum length 16cm. Monognathus. ORDER NOTACANTHIFORMES (ALBULIFORMES) Bonefish, Halosaurs, Deep-Sea Spiny Eels. Mandibular sensory canal open and lying in the dentary and angular bones. SUBORDER ALBULOIDEI Body herring-like; upper jaw does not extend as far as the front of the eye; mouth inferior. Maximum length about 1m. FAMILY ALBULIDAE Bonefishes. Marine; tropical seas. Albula,
Istieus. SUBORDER NOTACANTHOIDEI Body eel-like; anal fin merged with the reduced tail. FAMILY HALOSAURIDAE Halosaurs. Deep sea and worldwide. No spines; lateral line extending length of the body. Halosaurus,
Halosauropsis, Aldrovandia, Echidnocephalus. FAMILY NOTACANTHIDAE Spiny Eels. Deep sea; worldwide. Dorsal fin extends beyond the anus; spine-like rays (up to 3) in each pelvic fin. Lipogenys,
Polycanthonotus, Notacanthus. ORDER ELOPIFORMES Tarpons and tenpounders. Body slender; pelvic fins in the middle of the body; caudal fin deeply forked; upper jaw extending past eye; mouth terminal or superior; larvae small. FAMILY ELOPIDAE Tenpounders (Ladyfishes). Marine (rarely brackish or freshwater); tropical and subtropical. Body not laterally compressed; pelvic fin below or posterior to dorsal fin. Maximum length 1m. Elops. FAMILY MEGALOPIDAE Tarpons. Mainly marine; tropical or subtropical. Body compressed laterally; mouth terminal or superior. Maximum length 2.4m. Megalops
(=Tarpon) OTOCEPHALA – HERRINGS AND CARP This group
includes the Clupeomorpha and the Ostariophysi. ORDER
CROSSOGNATHIFORMES+ Incertae Sedis
with apparent affinities to both elopomorphs and otocephala, and likely sisters
to the Otocephala (Nelson 2006). Marine
fishes. Cretaceous
and one genus extending into the Eocene. Europe, North America, SUBORDER
CROSSOGNATHOIDEI Premaxilla
very small; palate without teeth; palatine long. FAMILY
CROSSOGNATHIDAE Apsopelix,
Crossognathus. SUBORDER
PACHYRHIZODONTOIDEI No
antorbitals FAMILY
NOTELOPIDAE Notelops. FAMILY
PACHYRHIZONTIDAE Elopopsis,
Greenwoodella, Pachyrhizodontus, Pachyrhizodus, Platinx (extends into Eocene),
Rhacolepis. These have a connection between the swim bladder and the inner ear. Many are armored with scutes both predorsal and ventral, a condition called double armored. Upper Cretaceous to present (Lower Cretaceous?) ORDER
ELLIMMICHTHYIFORMES+ Connection
between bladder and inner ear incomplete; patch of teeth on parasphenoid similar
to Osteoglossum.
Both dorsal and ventral scutes; some were deep bodied. FAMILY
PARACLUPEIDAE (ELLIMMICHTHYIDAE) Lower
Cretaceous to Middle Eocene; freshwater and marine. Armigatus,
Diplomystis, Sorbinichthys, Triplomystus, Paraclupea, Ellimma, Ellimmichthys. ORDER CLUPEIFORMES Herrings. Recessus lateralis (chamber in in which otophysic canal merges with other sensory canals) present; no parasphenoid teeth; no leptocephalus; planktivores with straining gill rakers. SUBORDER DENTICIPITOIDEI FAMILY DENTICIPITIDAE Denticle
Herrings. Freshwater; rivers of Miocene to present. Denticeps,
Paleodenticeps+ SUBORDER CLUPEOIDEI 19 fin caudal fin rays; FAMILY PRISTIGASTERIDAE Longfin
Herrings. Mainly marine; a few freshwater forms in South America and Southeast
Asia; tropical and subtropical seas; Subfamily
Pelloninae: Chirocentrodon, Ilisha,
Neoopisthopterus, Pellona, Plioteostoma. Subfamily
Pristigasterinae: Odontognathus,
Opisthopterus, Pristigaster, Raconda. FAMILY ENGRAULIDAE Anchovies. Marine (rarely freshwater); Atlantic, Indian, pacific oceans. Jaws extending well behind the eye; snout blunt; mostly planktivores. Maximum length 37cm. Subfamily
Coiliinae: Coilia, Lycothrissa,
Papuengraulis, Setipinna, Thryssa. Subfamily Engraulinae: Amazonsprattus, Anchoa, Anchovia, Anchoviella, Cetengraulis, Encrasicholina, Engraulis, Jurengraulis, Lycengraulis, Pterengraulis, Stolephorus. FAMILY CHIROCENTRIDAE Wolf Herring. Marine; Indian and western Pacific. Body elongate; fang-like jaw teeth; pelvic fins small. Voraceous carnivores. Maximim length 1m. Upper Cretaceous to present Chirocentrus, Gastroclupea+. FAMILY CLUPEIDAE Herrings (Shads, Sprats, Sardines, Pilchards, Menhadens). Mostly marine; some freshwater and anadromous; global but mostly tropical. Mouth terminal; teeth small or absent. Maximum length 60cm. Subfamily
Dussumieriinae (Round Herrings): Pelvic scutes w-shaped: Dussumieria, Etrumeus, Jenkinsia, Stratelloides. Subfamily Sundasalanginae (Sundaland Noodlefishes): Body transparent; scaleless; dorsal and anal fins posterior. Maximum length 28mm. Freshwater Borneo. Sundasalanx. Subfamily
Pellonulinae (Freshwater Herrings): pre and post pelvic scutes absent; mostly
freshwater; most species in lakes and rivers of Middle
Paleocene to present: Clupeichthys,
Clupeoides, Congothrissa, Cynothryssa, Ehirava, Hyperlophus, Limnothrissa,
Microthrissa, Pellonula, Potamalosa, Potamothrissa, Spratellomorpha,
Stolothrissa, Knightia+. Subfamily
Clupeinae (Sardines and Sprats): Amblygaster,
Clupea, Clupeonella, Escualosa, Harengula, Herklotsichthys, Lile, Opisthonema,
Sardina, Sardinella, Sardinops, Sprattus, Gosiutichthys+. Subfamily
Alosinae (Shads): Upper jaw with distinct notch, terminal: Alosa, Brevoortia, Ethmalosa, Ethmidium, Gudusia, Hilsa, Tenualosa. Subfamily
Dorosomatinae (Gizzard Shads): Upper jaw with notch, inferior: Anodontostoma,
Clupanodon, Dorosoma, Gonialosa, Konosirus, Nematalosa. Dermopalatine absent; swim bladder present (usually two chambers); upper jaw protractile; pelvic fins abdominal. Fright reaction by release of a pheromone. ANOTOPHYSI ORDER GONORHYNCHIFORMES Milkfishes. First three vertebrae specialized and associated with cephalic ribs (primitive Weberian apparatus); mouth small; jaws toothless. SUBORDER CHANOIDEI FAMILY CHANIDAE Milkfishes. Marine and brackish; tropical and subtropical; Indian and Pacific oceans. Mouth cleft and small; no teeth in the jaws. Subfamily
Rubiesichthyinae+. Lower Cretaceous
taxa: Gordichthys ( SubfamilyChaninae:
Body compressed; mouth not protractile. Lower
Cretaceous to the present: Chanos, Dastilbe
(South America), Parachanos (Africa), Tharrhias
( SUBORDER GONORYNCHOIDEI Beaked Sandfishes. Marine; Indian and Pacific oceans. Body long; mouth inferior; protractile jaw; single barbell; ctenoid scales; fins posterior. Late Cretaceous to present (North
America, Europe; Gonorynchus, Notogoneus+, Charitosomus+,
Judeichthys, Ramallichthys+, Charitopsis+. SUBORDER KNERIOIDEI Swim bladder present and used in respiration in some species. FAMILY KNERIIDAE Freshwater;
tropical Africa and Cromeria,
Grasseichthys, Kneria, Parakneria. FAMILY PHRACTOLAEMIDAE Snake
Mudheads. Freshwater; tropical Phractolaemus. OTOPHYSI Bones (called Weberian ossicles) transmit vibrations from the swim bladder to the inner ear. Lower Cretaceous to present. ORDER CYPRINIFORMES Carps. Kinethmoid ( a bone
between the premaxillae) present; always toothless; head usually scaleless.
Greatest diversity in SUBORDER CYPRINOIDEA FAMILY CYPRINIDAE Minnows and
Carps. Freshwater; rarely brackish; North America, Africa, Eocene to present Subfamily
Acheilognathinae (Bitterlings) Subfamily
Cultrinae: eastern Subfamily Cyprininae (Crucian Carp, Goldfish, Common Carp, Koi): Carassius, Cyprinus. Subfamily Barbinae (Barbels, Barbs, and Snow Trouts): Barbus, Diptychus, Pseudobarbus, Puntius, Schizothorax, Sinocyclocheilus. Subfamily Squaliobarbinae (Grass Carp): Ctenopharyngodon, Mylopharyngodon, Squalidobarbus. Subfamily Tincidae (Tench): Tinca. Subfamily Xenocyprinidae (Bighead Carp and Silver Carp). Miocene to present. Aristichthys, Hypophthalmichthys, Xenocypris, Eoxenocypris+, Xenocyproides+. Subfamily
Gobioninae (Gudgeons): Subfamily Rasborinae (Danioninae), Africa and Southern Eurasia: Amblypharyngodon, Aspidoparia, Barilius, Chela, Danio (Brachydanio), Danionella, Engraulicypris, Esomus, Leptocypris, Macrochirichthys, Mesobola, Neobola, Opsaridium, Opsariichthys, Opsarius, Oxygaster, Raiamas, Rasbora, Rastrineobola, Salmostoma, Tanichthys, Thryssocypris, Zacco. Subfamily
Leuciscinae North American taxa: Acrochelius,
Agosia, Algansea, Aztecula, Campostoma, Clinostomus, Couesius, Cyprinella,
Dionda, Eremichthys, Erimonax, Erimystax, Exoglossum, Gila, Hemitremia,
Hesperoleucus, Hybognathus, Hybopsis, Iothchthys, Lavinia, Lepidomeda, Luxilus,
Lythrurus, Macrhybopsis, Margariscus, Meda, Moapa, Mylocheilus, Mylopharodon,
Nocomis, Notemigonus, Notropis, Opsopoeodus, Oreganichthys, Orthodon,
Phenacobius, Pimephiles, Plagopterus, Platygobio, Pogonichthys, Pteronotropis,
Ptychocheilus, Relictus, Rinichthys, Richardsonius, Semotilus, Snyderichthys,
Yuriria. Eurasia taxa: Aaptosyax, Abramis, Alburnoides, Alburnus, Aspius, Blicca, Chalcalburnus, Chrondrostoma, Elopichthys, Eupallasella, Leuciscus (Idus), Luciobrama, Luciocyprinus,, Oreoluciscius, Pelecus, Pseudophoxinus, Rutilus, Scardinius, Tribolodon, Vimba. Cyprinid taxa with uncertain affinities: Acrossocheilus, Balantiocheilos, Bangana, Boraras, Capoeta, Catlocarpio, Cirrhinus, Crossocheilus, Cyclocheilichthys, Cyprinion, Epalzeorhynchos, Garra, Gibelion, Gymnocypris, Hampala, Oreinus, Phreatichthys, Poropuntius, Rectoris, Rohtee, Semiplotus, Tor, Varicorhinus. FAMILY PSILORHYNCHIDAE Mountain
Carps. Freshwater mountain streams; Psilorhynchoides,
Psilorhynchus. SUBORDER COBITOIDEA Opisthotic is absent. FAMILY GYRINOCHEILIDAE Algae
Eaters. Freshwater mountain streams; Gyrinocheilus. FAMILY CATOSTOMIDAE Suckers. Freshwater; China, Siberia, North America. One row of 16 or more pharyrngeal teeth. Maximum length 1m. Subfamily Myxocyprininae; deep-bodied fish of Yangtse and Hwang Ho river systems: Myxocyprinus. Subfamily Ictiobinae (Quillback, Carpsuckers, and Buffaloes), Canada to Guatemala: Carpoides, Ictiobus. Subfamily Cycleptinae (Blue Suckers), Mississippi Basin and other drainages of the Gulf coast of the USA and Mexico: Cycleptus. Subfamily Catostominae (Suckers), Siberia to Alaska and south to Mexico: Catostomus, Chasmistes, Deltistes, Xyrauchen, Erimyzon, Minytrema, Hypentelium, Thoburnia, Moxostoma. FAMILY COBITIDAE Loaches.
Freshwater; Eurasia and northwestern Subfamily Cobitinae: one pair of rostral barbels: Acanthopsis, Acanthopsoides, Acanthophthalmus, Acantopsis, Cobitis, Enobarbus, Kichulchoia, Kottelatlimia, Lepidocephylichthys, Lepidocephalus, Misgurnus, Neoeucirrhichthys, Niwaella, Pangio, Serpenticobitis, Somileptus. Subfamily Botiinae. Two pairs of rostral barbels: Botia, Chromobotia, Leptobotia, Parabotia, Sinibotia, Syncrossus, Yasuhikotakia. FAMILY BALITORIDAE (HOMALOPTERIDAE) River
Loaches. Freshwater; Subfamily
Nemacheilinae; Prepalatine present; no spine under the eye; loaches of Subfamily
Balitorinae (Flat Loaches) Loaches of swift mountain streams in ORDER CHARACHIFORMES Characins. Teeth well-developed; adipose fin present; body usually scaled (ctenoid scales); upper jaw not truly protractile; with pharyngeal teeth; no barbels. Maximum length 1.4m. SUBORDER CITHARINOIDEI Teeth bicuspidate. FAMILY CITHARINIDAE Citharinids.
Freshwater; Citharinus,
Citharinops, Citharidium. SUBORDER CHARACOIDEI FAMILY PARODONTIDAE Parodontids.
Freshwater; benthic fishes of mountain streams of eastern Apareiodon,
Parodon, Saccodon. FAMILY CURIMATIDAE Toothless
Characiforms. Freshwater; Curimata,
Curimatella, Curimatopsis, Cyphocharax, Potamorhina, Psectrogaster,
Pseudocurimata, Steindachnerina. FAMILY PROCHILODONTIDAE Flannel-Mouth
Characiforms. Freshwater; Ichthyoelephas,
Prochilodus, Semaprochilodus. FAMILY ANOSTOMIDAE Toothed
Headstanders. Freshwater; southern Central America and Abramites,
Anostomoides, Anostomus, Gnathodolus, Laemolyta, Leprellus, Pseudanos, Rhytiodus,
Sartor, Schizodon, Synaptolaemus. FAMILY CHILODONTIDAE Headstanders.
Freshwater; northern Caenotropus,
Chilodus FAMILY CRENUCHIDAE South
American Darters. Freshwater; eastern Subfamily Crenuchinae: Crenuchus, Poecilocharax. Subfamily
Characidiinae: Ammocryptocharax,
Characidium, Elachocharax, Geryichthys, Klausewitzia, Leptocharacidium,
Melanocharacidium, Microcharacidium, Odontocharacidium, Skiotocharax. FAMILY HEMIODONTIDAE Hemiodontids.
Freshwater; pelagic in northern Subfamily Anodontinae: Anodus, Micromischodus. Subfamily Hemiodontinae: Hemiodus, Argonectes, Bivibrachia. FAMILY ALESTIIDAE (ALESTIDAE) African
Tetras. Freshwater; Alestes, Brycinus, Bryconaethiops, Clupeocharax, Hemigrammopetersius, Hydrocynus, Ladigesia, Micralestes, Nannopetersius, Petersius, Phenacogrammus, Rhabdalestes, Tricuspidalestes. FAMILY GASTEROPELECIDAE Freshwater
Hatchetfishes. Freshwater; Carnegiella,
Gastropelecus, Thoracocharax. FAMILY CHARACIDAE Characins.
Freshwater, Subfamily
Agoniatinae. Subfamily
Clupeacharacinae. Subfamily
Iguanodectinae. Subfamily
Bryconinae: Subfamily
Serrasalminae (Pacus, Silver Dollars, Piranhas): Subfamily
Aphyocharacinae: Subfamily
Characinae: Southern Mexiso to Subfamily
Stethaprioninae (Silver Dollar Tetras): Subfamily
Tetragonopterinae: Subfamily
Rhoadsiinae: Subfamily
Cheirodontinae: Subfamily
Glandulocaudinae: FAMILY ACESTRORHYNCHIDAE Acestrorhynchids.
Freshwater; |
