''Anstisia rosea'', the karri or roseate frog is a species in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

, Myobatrachidae. It is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

to Southwest Australia.

Taxonomy

It was formerly classified in the genus '' Geocrinia'', but was reclassified into the new genus '' Anstisia'' in 2022. The ''Geocrinia'' roseate frogs were previously placed in the genus ''

Crinia ''Crinia'' is a genus of frog, native to Australia, and part of the family Myobatrachidae. It consists of small frogs, which are distributed throughout most of Australia, excluding the central arid regions. Many of the species within this genu ...

'' by Harrison. It is most easily distinguished from the 5 congeners of the region (3 ''Anstisia'' and 1 ''Geocrinia'' species) by the rosy glow of the belly, as indicated in the name.

Description

''Anstisia rosea'' is very similar in appearance to three other ''Anstisia'' species; '' A. alba'', '' A. lutea'' and '' A. vitellina''. The usually discrete vomerine teeth of the species are evident in this species. Its colouring, largely brown, perhaps mottled, reveals another distinction between the species. The smooth skin of the creature, slightly tubercular on the upper parts, is a rosy pink below. This may also be flecked or mottled. The male has a dark to black throat, and the discrete darker markings are shared by both species. It is generally 25 mm long when adult.

Habitat and distribution

The frog is restricted to the higher rainfall karri forests of the

Warren bioregion Warren, also known as Karri Forest Region and the Jarrah-Karri forest and shrublands ecoregion, is a biogeographic region in southern Western Australia. Located in the southwest corner of Western Australia between Cape Naturaliste and Albany, i ...

at the southwest tip of the continent. Streams flow into and by the

Warren River The Warren River is a tidal extension of the Palmer River in the U.S. state of Rhode Island. It flows approximately 6.5 km (4 mi). There are no dams along the river's length. Course The river begins where the Palmer River widens just ...

, and the permanent moisture found there is the haven and restraint. The high rate of endemism in the result of the lack of

motility Motility is the ability of an organism to move independently, using metabolic energy. Definitions Motility, the ability of an organism to move independently, using metabolic energy, can be contrasted with sessility, the state of organisms th ...

in the species.

Reproduction

Spring and summer bring drive to form

amplexus Amplexus (Latin "embrace") is a type of mating behavior exhibited by some externally fertilizing species (chiefly amphibians and horseshoe crabs) in which a male grasps a female with his front legs as part of the mating process, and at the same ...

, and the poorly travelled males will cry for a mate with four beats of the generic 'tk'. Here the frog remains amongst the depressions and recesses, the female leaving her eggs amidst the fallen timber and dense vegetation of the lush forests. The young will emerge from the degrading gelatinous spawn as complete froglets, never swimming in more than the damp floor of their abode.

References

* Amphibians described in 1927 Amphibians of Western Australia Frogs of Australia Anstisia Taxonomy articles created by Polbot Endemic fauna of Southwest Australia Warren bioregion {{WesternAustralia-stub