''Triops australiensis'', sometimes referred to as a shield shrimp, is an Australian species of the tadpole shrimp '' Triops''.

Distribution

''Triops australiensis'' has a wide distribution across Australia, excluding the northernmost parts of

Western Australia Western Australia (commonly abbreviated as WA) is a state of Australia occupying the western percent of the land area of Australia excluding external territories. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to th ...

, and

Queensland ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , establishe ...

. It is also absent from

Tasmania ) , nickname = , image_map = Tasmania in Australia.svg , map_caption = Location of Tasmania in AustraliaCoordinates: , subdivision_type = Country , subdi ...

in the south, where it is replaced by ''

Lepidurus apus ''Lepidurus apus'', commonly known as a tadpole shrimp, is a notostracan in the family Triopsidae, one of a lineage of shrimp-like crustaceans that have had a similar form since the Triassic period and are considered living fossils. This specie ...

''. The two species can be distinguished by the presence of a supra-anal plate between the caudal rami at the end of the

abdomen The abdomen (colloquially called the belly, tummy, midriff, tucky or stomach) is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the to ...

in ''L. apus'', which is lacking in ''T. australiensis''.

Biology

''T. australiensis'' inhabits temporary pools of water in the arid regions of the

Australian outback The Outback is a remote, vast, sparsely populated area of Australia. The Outback is more remote than the bush. While often envisaged as being arid, the Outback regions extend from the northern to southern Australian coastlines and encompass a n ...

. When desiccated pools fill with water, the resting eggs hatch into nauplii, and rapidly develop to adulthood. Reproduction succeeds within a few weeks of hatching. Adults achieve a maximum size of around , which is considered large for a tadpole shrimp.

Water chemistry

''Triops australiensis'' can tolerate a pH of 7–9, and can live in both

hard Hard may refer to: * Hardness, resistance of physical materials to deformation or fracture * Hard water, water with high mineral content Arts and entertainment * ''Hard'' (TV series), a French TV series * Hard (band), a Hungarian hard rock supe ...

and soft water, but the eggs of ''T. australiensis'' are more likely to hatch in water with a low mineral content.

References

External links

* {{Taxonbar, from=Q3313727 Notostraca Freshwater crustaceans of Australia Endemic fauna of Australia Crustaceans described in 1895 Taxa named by Walter Baldwin Spencer