Resurrection of the snailfish genus Allinectes (Teleostei: Cottiformes: Liparidae) for seven North Pacific species, including descriptions of three new species from Alaska

The subgenus Allinectes was established by Jordan & Evermann (1898) for the single species Careproctus ectenes. I elevate Allinectes to genus, based on the elongate anterior dorsal-fin rays followed by a distinct notch found in both sexes of all its members. With A. ectenes, I allocate six additional species to Allinectes: A. curilanus, A. attenuatus, A. pycnosoma, and three new species, described herein.

The three new species, A. istiophorus, A. busbyi, and A. nanstanorum, are described on the basis of individuals collected in the Aleutian Islands and Bering Sea during fisheries resource assessment surveys conducted by the U.S. National Marine Fisheries Service. Each is most similar to A. ectenes from which they are distinguished by a dark peritoneum, lower counts of vertebrae and dorsal- and anal-fin rays, and several morphometric characters, including longer gill slits, a larger pelvic disk, and typically shorter distances from disk to anus.

Allinectes istiophorus is distinguished from Allinectes nanstanorum by having a paler body, pale stomach, deeper and more robust body, and longer first dorsal-fin ray. Allinectes busbyi differs from both A. nanstanorum and A. istiophorus by its strongly protruding snout and robust body. Described from 88 specimens, Allinectes istiophorus is found widely within the Aleutian Islands, from west of Attu Island in the west to north of Akutan Island in the east, and in the Bering Sea west and south of the Pribilof Islands at depths of 117 to 762 m.

The deeper dwelling Allinectes nanstanorum is described from two specimens found in the Bering Sea on the upper continental slope near the Pribilof Islands at depths of 866 and 1172 m. Allinectes busbyi is described from a single specimen collected in the central Aleutian Islands in Seguam Pass at 458 m depth. Allinectes curilanus is redescribed from the types collected from the Kuril Islands and 30 additional specimens, all taken in the Aleutian Islands from west of Attu Island to the Islands of Four Mountains in the east at depths of 240 to 471 m.

The five known specimens of A. ectenes, taken north of Unalaska Island and on Bowers Bank at 494 to 640 m depth, the holotype and only known specimen of A. attenuatus, taken off Agattu Island at 881 m depth, and the holotype and only known specimen of A. pycnosoma, taken off Simushir Island at 419 m depth in the Kuril Islands, are also redescribed.