A revision of the genus Halectinosoma (Harpacticoida: Ectinosomatidae): a reappraisal of H. sarsi (Boeck) and related species

Ectinosomatid material was examined from extensive collections around the British Isles and from several additional world localities and museum collections, permitting a revision of the genus Halectinosoma. This paper describes 12 morphologically similar species and erects five new species. H. sarsi (Boeck) is regarded as species incertae sedis, while H. sarsi sensu Sars (1904) is redescribed as H. pseudosarsi sp. nov.; H. sarsi sensu T. & A. Scott (1894) is synonymized with H. canaliculatum (Por). H. propinquum is regarded as a junior subjective synonym of H. chrystalli (T. Scott). H. clavatum (Sars) is resurrected, having previously been regarded as a synonym of H. brunneum (Brady). A key for the identification of females belonging to this group of species is provided.