Gadidae
by A. N. Svetovidov
1-3 dorsal and 1 or 2 anal fins, a separate caudal fin. Fins spineless. A barbel on chin usually present. First vertebra and neural spine attached to skull. Exoccipitals without fontanelles, swimbladder with two anterior slender processes, which have no contact with the auditory organs. Inter-orbital septum and the canal for the olfactory nerves membranous below. Neurocranium with a wide opening anteriorly. Orbito-mesethmoid part of the skull considerably longer than the posterior part. Head of vomer toothed. 4 or 5 pectoral pterygials.
Marine fishes (except Lota lota), but a few occurring in brackish water and entering mouths of rivers. Shallow and coastal waters or open sea in great depths, at bottom, in midwater or pelagic, most on continental shelf. Mostly gregarious in large shoals, or solitary, sedentary or making considerable seasonal or spawning migrations. Juveniles of most of inshore species are found closer to shore than adults. Adults of large gadids feed on fish, molluscs, echinoderms, large crustaceans; immature fishes and small species on small crustaceans. Time of spawning variable, mainly in second half of winter and spring, sometimes in summer, at low temperatures, 1-10° C, rarely below 0° C; fecundity very great; in large gadids several or up to 60 million eggs, in small species 6,000-90,000; eggs non-adhesive, buoyant, in a few species demersal; larvae pelagic or mesopelagic; development of eggs from a week to a month. Extremely important group of food fishes,
particularly in northern waters and especially in North Atlantic.
Mainly in cold waters of northern hemisphere, partly in subtropical waters and in southern hemisphere. Because of the feeding and spawning migrations, and because of the pelagic eggs and long pelagic larval life, they are widely dispersed by means of ocean currents, so many species are widely distributed.
Genera 22; in Clofnam area 21.
Recent revisions: Svetovidov (1948, 1962.)
Gadinae
[subfamily]
3 dorsal and 1 anal fin separated or in contact. Frontals united. Pelvic fins in larvae consist of more than 3 rays and are not elongated.
Lotinae
[subfamily]
1 or 2 dorsal fins and 1 anal fin; first dorsal fin sometimes reduced to a single ray. Pelvic fins in larvae consist of 3 rays and are usually greatly elongated. Frontals separate (united in Phycis and Urophycis).