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

It was described in 1918 by Australian arachnologists William Joseph Rainbow and Robert Henry Pulleine.

[1][2] The species occurs in south-west Western Australia in open forest habitats, from the valleys of the Darling Scarp southwards to Bunbury and south-eastwards to Albany.

The type locality is Kings Park in Perth.

They construct burrows with trapdoors in wet creek banks, the flood flats of watercourses and on patches of open ground in clay soils.