Tags: Arachnid.
Idiosoma is also the terminus for an anatomical structure of mites.Idiosoma is a genus of trapdoor spiders in the family Idiopidae with three species found only in Western Australia.The genus was transferred from Ctenizidae to Idiopidae in 1985.Idiosoma nigrum commonly called the Black rugose trapdoor spider can grow up to 30 mm long. Males reach a body size of up to 18 mm. The skin of their opisthosoma is hardened with a flattened end and deep grooves running along the sides.