PARACANTHOPTERYGIAN

any member of the superorder Paracanthopterygii, a group of bony fishes comprising six orders and containing about 1,160 species. Well-known forms include the anglerfish and the commercially valuable cod, but the toadfish, clingfish, and beardfish also belong to this group. Most paracanthopterygians are found worldwide in oceans; only the trout perch of North America lives solely in freshwater. The codfish, which grows up to 2 m (about 7 feet) long, is the largest species; they may weigh as much as 90 kg (200 pounds). Some goosefish may also reach about two metres in length, with a body weight of 35 kg (75 pounds). The distinguishing features of paracanthopterygians are a distinctive jaw musculature, the structure of the caudal (tail) vertebrae, and the placement of the pelvic fins in the middle of the body or toward the head. Fossil forms have been found that date from the Cretaceous period (144 million to 66.4 million years ago). any member of the superorder Paracanthopterygii, a predatory, primarily marine group that forms one of about six major branches of the Teleostei, or bony fishes, the dominant modern aquatic vertebrates. Approximately 1,160 living species of paracanthopterygian fishes have been described. They range in length from just a few centimetres to roughly two metres (more than six feet). Well-known forms include the anglerfish and the cod. In general body form there is considerable diversity, but ichthyologists have classed the Paracanthopterygii as a discrete group, largely on the basis of a distinctive musculature of the jaws, the structure of the caudal (i.e., at the tail end) vertebrae, and the placement of the pelvic fins (they are usually in the midbody region or even farther toward the head). The Paracanthopterygii comprises six orders: Batrachoidiformes, or toadfishes, about 45 species; Gadiformes, or codfishes, about 800 species; Gobiesociformes, or clingfishes, about 100 species; Lophiiformes, or anglerfishes, about 210 species; Percopsiformes, or trout-perches, about eight species; and Polymixiiformes, or beardfishes, three species. Most of the orders are primarily marine, with worldwide distribution; the percopsiforms, however, occur only in fresh waters of North America. Batrachoidiforms and gobiesociforms occur mainly in tropical and temperate shallow water along continental coasts and to a limited extent in fresh water. Gadiforms are represented by both shallow-water and deep-sea types. The most widely known gadiforms are the commercially important species and the only economically important paracanthopterygians: the true cods (Gadus), hakes (Merluccius, Urophycis), haddocks (Melanogrammus), pollocks (Pollachius), and whitings (Merlangius). All are abundant in waters of the continental shelf of the North Atlantic, where they have been commercially fished for centuries from both Europe and North America. Lophiiforms live in shallow waters of tropical reefs as well as in the ocean depths. Polymixiiforms occur at moderate depths in most warm seas, generally near continents. The largest of the Paracanthopterygii are the codfishes, which grow to about two metres in length and attain weights that may exceed 90 kilograms (about 200 pounds). Certain goosefishes (Lophiiformes) reach a length of about two metres and a body weight of 35 kilograms (about 75 pounds); other lophiiforms are as small as 21/2 centimetres (about one inch) long. Batrachoidiforms grow to about 30 centimetres (one foot) in length, gobiesociforms to about eight centimetres (three inches). The largest percopsiforms are about 15 centimetres (six inches) long. Polymixiiforms reach no more than 30 centimetres in length. Additional reading General C.M. Breder and D.E. Rosen, Modes of Reproduction in Fishes (1966); E.S. Herald, Living Fishes of the World (1961, reprinted 1972). Faunal J.E. Bhlke and C.C.G. Chaplin, Fishes of the Bahamas and Adjacent Tropical Waters, 2nd ed. (1993); W.A. Clemens and G.V. Wilby, Fishes of the Pacific Coast of Canada, 2nd ed. (1961); A.H. Leim and W.B. Scott, Fishes of the Atlantic Coast of Canada (1966); T.C. Marshall, Fishes of the Great Barrier Reef and Coastal Waters of Queensland (1964); Y. Okada, Fishes of Japan, rev. ed. (1965); T.D. Scott, The Marine and Freshwater Fishes of South Australia, 2nd ed. (1974); J.L.B. Smith, The Sea Fishes of Southern Africa, 5th ed. (1965); M. Weber and L.F. de Beaufort, The Fishes of the Indo-Australian Archipelago (191162), a multivolume work; A. Wheeler, The Fishes of the British Isles and North-West Europe (1969). Specific (Batrachoidiformes): B.B. Collette, A Review of the Venomous Toadfishes, Subfamily Thalassophryninae, Copeia, pp. 846864 (1966); C.R. Gilbert, Western Atlantic Batrachoidid Fishes of the Genus Porichthys, Including Three New Species, Bull. Mar. Sci., 18:671730 (1968). (Gadiformes): D.C. Arnold, A Systematic Revision of the Fishes of the Teleost Family Carapidae (Percomorphi, Blennioidea), with Descriptions of Two New Species, Bull. Br. Mus. Nat. Hist. (Zool.), 4:245307 (1956); U. D'Ancona and G. Cavinato, The Fishes of the Family Bregmacerotidae (Dana Rep. 64) (1965); N.B. Marshall, Systematic and Biological Studies of the Macrourid Fishes (Anacanthini-Teleosteii), Deep Sea Res., 12:299322 (1965); J.G. Nielsen, Systematics and Biology of the Aphyonidae (Pisces, Ophidioidea), Galathea Rep., 10:190 (1969); D.W. Strasburg, Description of the Larva and Familial Relationships of the Fish Snyderidia canina, Copeia, pp. 2024 (1965); A.N. Svetovidov, Gadiformes (1962; originally published in Russian, 1948). (Gobiesociformes): J.C. Briggs, A Monograph of the Clingfishes (Order Xenopterygii), Stanford Ichthyol. Bull., 6:1224 (1955). (Lophiiformes): E. Bertelsen, The Ceratioid Fishes (Dana Rep. 39) (1951); M.G. Bradbury, The Genera of Batfishes, Copeia, pp. 399422 (1967); L.P. Schultz, The Frogfishes of the Family Antennariidae, Proc. U.S. Natn. Mus., 107:47105 (1957). (Percopsiformes): M.B. Trautman, The Fishes of Ohio, with Illustrated Keys, rev. ed. (1981); L.P. Woods and R.F. Inger, The Cave, Spring, and Swamp Fishes of the Family Amblyopsidae of Central and Eastern United States, Am. Midl. Nat., 58:232256 (1957). (Polymixiiformes): E.A. Lachner, Populations of the Berycoid Fish Family Polymixiidae, Proc. U.S. Natn. Mus., 105:189206 (1955). Systematic W.A. Gosline, Functional Morphology and Classification of Teleostean Fishes (1971); D.E. Rosen and C. Patterson, The Structure and Relationships of the Paracanthopterygian Fishes, Bull. Am. Mus. Nat. Hist., 141:357474 (1969).