A new genus of Parabathynellidae (Crustacea: Bathynellacea) in New South Wales,Australia

A new genus and species of the family Parabathynellidae, Octobathynella peelensis gen. nov. sp. nov., is described from New South Wales, Australia. The new genus displays several exclusive characters: a very large and distinctive male thoracopod VIII with one crest-like projection containing two lobules on the basipod; and four aesthetascs on segments six and seven of the antennule. It also has several combinations of characters that make it unique in the Parabathynellidae, specifically that: the antennule is eight-segmented (a new character in the Australian species); there are seven segments in the antenna; the labrum has 18–20 teeth; the exopod of thoracopod I has three to four segments and the exopod of thoracopod II has four segments; the endopod has one dorsal seta on the first and second segments and the epipod is absent on thoracopod I; pleopods are absent; the endopod of the male thoracopod VIII has two setae and the exopod has setules; there are 10–12 spines on the sympod, three or four spines on the endopod and five setae on the exopod of the uropod. The new genus and species is placed into context with all known Bathynellacea in Australia, and the biogeographic patterns are discussed for this ancient group of subterranean crustaceans.