Revision of Holidoteidae, an endemic southern African family of Crustacea, and re-appraisal of taxa previously included in its three genera (Isopoda: Valvifera)

Abstract

The Holidoteidae Wägele, 1989, a family of three genera confined to southern Africa, are reviewed. Diagnoses are given for Austroarcturus Kensley, 1975, Holidotea Barnard, 1920 and Neoarcturus Barnard, 1914. Their type species are re-illustrated. Keys and brief diagnoses are provided to the six species of Austroarcturus, all from shelf depths (A. africanus Kensley, A. foveolatus Kensley, A. laevis (Kensley), A. quadriconis (Kensley), A. dayi (Kensley), A. similis (Kensley)) and the nine species of Neoarcturus, from slope depths (N. barnardi (Kensley), N. biserialis (Kensley), N. halei (Kensley), N. kensleyi n. sp., N. longispinus (Kensley), N. nordenstami (Kensley), N. ornatus (Kensley), N. oudops Barnard, N. youngi (Kensley)). Holidotea is monotypic, H. unicornis inhabiting the lower shelf. Southern African species of ' Microarcturus ' Nordenstam, 1933, a generic name without type species and therefore a nomen nudum, are placed in Austroarcturus or Neoarcturus. Non-southern African species (mostly Antarctic or subantarctic) assigned to ' Microarcturus ' or described as species of it are placed in other genera in Antarcturidae, Austrarcturellidae, Pseudidotheidae and Rectarcturidae. 'Microarcturus' mawsoni Hale, Arcturus hirticornis Monod and A. patagonicus Ohlin which were included in ' Microarcturus ' by Nordenstam, and 'M.' rugosus Nordenstam (herein redescribed) are placed in Fissarcturus Brandt. Three others are assigned to Mixarcturus Brandt: 'Microarcturus' abnormis Kussakin, Arcturus acanthurus Monod; and 'Microarcturus' digitatus Nordenstam (herein redescribed). The following, also from Antarctic and subantarctic waters, have also been placed in ' Microarcturus ' at various times and are reallocated to other genera: Antarcturus kilepoae Kussakin, Litarcturus stebbingi (Beddard); Rectarcturus kophameli (Ohlin); Austrarcturella oculata (Beddard); and Pseudidothea scutata (Stephensen). Four poorly known Australian species described by Whitelegge and included by Nordenstam in ' Microarcturus ' remain unclassifiable. A fifth, Arcturus serratulus, also placed in ' Microarcturus ', belongs in an undiagnosed new genus. 'Microarcturus' tannerensis Schultz belongs in another new genus, also as yet undiagnosed. Six Antarctic species, until now members of Neoarcturus, are not members of Holidoteidae and are assigned to the antarcturid genus Fissarcturus (F. elongatus (Brandt), F. minutus (Brandt), F. poorei (Kussakin and Vasina), F. robustus (Brandt), F. scelerosus (Brandt) and F. stebbingnordenstami (Brandt)). Neoarcturus fungifer Kussakin and Vasina is a probable member of Tuberarcturus and N. caecus Kussakin and Vasina is a member of Antarcturus. N. vinogradovae Kussakin and Vasina, N. cochlearicornis Kussakin and Vasina and N. paxillaris Kussakin and Vasina remain of doubtful generic affinities.