Derichthys Schmidt, 1930
Diagnosis: body elongate, scaleless, constricted between head and pectoral fins; anus slightly behind midpoint of body. Eyes well developed. Nostrils pore-like, dorsolateral, dividing snout into almost equal thirds. Mouth reaching or almost to posterior eye margin. Teeth small and conical, jaws with 3-5 irregular rows, diminishing posteriorly; a transverse band with 3-5 rows on premaxillae, continuous with those of maxillae; a horseshoe-shaped patch on vomer, separated from premaxillary teeth, sometimes with inner rudimentary teeth. Gill opening small, ventrolateral, well separated. Dorsal and anal fins confluent with caudal fin; dorsal fin origin far behind pectoral fins; dorsal fin markedly lower in about last third of caudal region. Lateral line: 80-90 pores; 3 supra-temporal pores; tubular ethmoidal pores at tip of snout. Vertebrae: total 126-134; abdominal 59-61. Colour: tawny olive to mouse grey with glints of bluish sheen on neck; fins slightly pigmented but almost transparent. Size: to 31.5 cm.
Habitat: bathypelagic, down to 2,000 m. Food: carnivorous (Natania crustaceans among other prey). Reproduction: warm hydrological season. Leptocephali (L. anguilloides Schmidt, 1916) with metamorphic stages, length of larval life unknown.
Distribution: eastern North Atlantic. Elsewhere, Central and South Atlantic, also Indian and Pacific Oceans.
Species 1.
Recent revision: Castle (1970).
Species of this genus in the program:
Derichthys serpentinus