The Australian shrimps of the genus Paratya are widespread throughout eastern Australia from Queensland to South Australia and in Tasmania (Cook et al., 2006; Williams, 1977; Williams & Smith, 1979) (Fig 1). The first species of Paratya from Australia, Paratya australiensis, was described by Kemp (1917).
Since first being described the taxonomic history of Paratya in Australia has been one of confusion due to the high morphological variability within material collected from a wide range of locations.
Riek (1953) recognised five taxa but Williams (1977) did not consider Riek’s revision to be valid and in a subsequent paper (Williams & Smith, 1979) all Riek’s taxa were formally synonymised with Paratya australiensis Kemp.
A series of papers on the genetic characteristics of Paratya (Baker et al., 2004a; Baker et al., 2004b; Cook et al., 2007; Hancock et al., 1998; Hurwood et al., 2003; Page et al., 2005) and which culminated in the paper by Cook et al. (2006) demonstrated nine distinct lineages over the geographical range of Paratya. A further lineage was discovered by McClusky (2007) from the south west of Victoria.
A key that links morphological and molecular data is presented enabling the identification of all the separate lineages of “Paratya australiensis”, with the exception of the one from SW Victoria. To avoid the variability caused by sexual dimorphism only female characteristics are presented here but the key seems to work for males too, but not all lineages have been compared.