Australia has more species of halophilic Anostraca than any other continent and most belong to the endemic genus Parartemia. The distributions of twelve described and 10 undescribed species of Parartemia have been mapped, based on 367 records. Western Australia (WA) has 13 species, South Australia (SA) seven, Victoria two and the remaining states and the Northern Territory (NT) have one each.
... [Show full abstract] Some species are widespread, including P. minuta in the inland of the eastern states, new species 'g' in northern and inland WA and the NT and P. cylindrifera and P. acidiphila in southern SA and southern WA. Many species are widespread in the Wheatbelt and/or Goldfields of WA (e.g. P. informis, P. longicaudata, P. serventyi, P. acidiphila and species 'a'). Eight species are known from six or fewer sites each in WA or SA. It is recommended that P. extracta and species 'c' should be assessed against IUCN categories and criteria as a threatened species. They are likely to be consistent with category "Vulnerable" due to secondary salinisation severely affecting their habitat and the declining number of populations. Parartemia species 'b', 'e' and 'x' should be assessed against the Western Australian Department of Environment and Conservation's criteria for listing as Priority species (Priority 1: Taxa with few, poorly known populations on threatened lands), due to the threat posed by secondary salinisation and/or few known locations. Parartemia contracta is already listed as a Priority 1 species, but is perhaps not as threatened as previously believed and so this should be reassessed. Others, particularly those in the WA Wheatbelt, are losing populations to salinisation, but are probably safe in smaller lakes in the upper catchments. In most cases of population extinction we believe that some combination of salinity change, pH decrease, and change to water permanency is involved. In order to provide a more suitable base for assessment of conservation significance and environmental requirements we recommend further surveys and monitoring of natural saline lakes and research on the ecophysiology of Parartemia species in Western Australia.