Redescription of Alona macracantha Smirnov and Timms, 1983 and its assignment to Maraura gen. nov. (Cladocera: Anomopoda: Chydoridae)

Three new species of the harpacticoid family Ameiridae are described from clean sand at high water neap tide on St Martin's Flat, Isles of Scilly. Ameiropsis martinis sp. nov. appears most closely related to A. australis Kunz, 1975 Kunz, H. 1975. Copepoda Harpacticoidea aus dem litoral des sudlichen Afrika. 1 Teil. Kiel Meeresforsch., 31(2): 179–212.  [Google Scholar] but can be distinguished from it by the shape of the rostrum and the armature of the operculum, female genital field and the male P5 baseoendopodal lobe. Sarsameira parexilis sp. nov. was originally identified as S. exilis T. and A. Scott, 1894 Scott, T. 1894. Additions to the fauna of the Firth of Forth. Part IV. 12th Annual Report of the Fisheries Board for Scotland, : 231–270.  [Google Scholar] but the females can be distinguished from S. exilis by their smaller body size and shape of the caudal ramus whilst the males can be distinguished by the 12-segmented antennule and four setae on the P5 baseoendopodal lobe. Ameira longispina sp. nov. is unique within the “Ameira” complex of genera and species because of the marked elongation of the inner spine on the basis of the male P1. This species is tentatively placed in Ameira Boeck, 1865, but has features which indicate that it probably occupies an intermediate position between this genus and Psammameira Noodt, 1952. The previously unknown males of Sarsameira perezi Bodin, 1970 Bodin, P. 1970. Copépodes Harpacticoides marins des environs de La Rochelle 1. Especes de la vase intertidale de Chatelaillon. Tethys, 2(2): 385–436.  [Google Scholar] and Nitocra elegans (T. Scott, 1905 Scott, T. 1905. On some new and rare Crustacea from the Scottish seas. 23rd Annual Report of the Fisheries Board for Scotland, : 141–153.  [Google Scholar]) are also described.