Idiosoma subtriste is a species of mygalomorph spider in the Idiopidae family.

It was described in 1877 by British arachnologist Octavius Pickard-Cambridge.

[1][2] The species occurs in South Australia, in the Mount Lofty and Flinders Ranges, in open scrub and woodland habitats.

[1][2] The spiders are fossorial, terrestrial predators.

This Idiopidae article is a stub.