Tyrannochthonius aridus is a species of pseudoscorpion in the Chthoniidae family.

It was described in 2008 by Australian arachnologists Karen Edward and Mark Harvey.

[1][2] The species occurs in North West Australia.

The type locality is Cave B6 on Barrow Island, off the Pilbara coast.

[1][2] The arachnids are cave-dwelling, terrestrial predators.