On Branchiopodataenia n. g., parasitic in gulls, and its type-species, B. Anaticapicirra n. sp. (Cestoda: Hymenolepididae).

Branchiopodataenia n. g. is established for hymenolepidid cestodes characterised by the presence of a specific morphological feature, a latch-like structure in the copulatory part of the vagina. Their life-cycles involve branchiopod crustaceans (Branchiopoda) as intermediate hosts and gulls as definitive hosts. The type-species of the genus, B. anaticapicirra n. sp. from gulls of Chukotka (Chaun lowlands) and Alaska (River Yukon, Cape Barrow), is described. It is established that B. arctowskii (Jarecka & Ostas, 1984) n. comb. (originally Hymenolepis ) has a bipolar distribution and is not endemic to the Antarctic. A description of B. arctowskii from the northern hemisphere and the principal characters of other known species of this genus, B. gvozdevi (Maksimova, 1988) n. comb. (originally Wardium ), B. haldemani (Schiller, 1951) n. comb. (originally Hymenolepis ) and B. pacifica (Spassky & Jurpalova, 1968) n. comb. (originally Wardium ), are included. A key to the species of Branchiopodataenia is also presented.