Tyrannochthonius garthhumphreysi 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 a borehole in limestone karst, 7 km north of the Chevron Texaco camp, on Barrow Island off the Pilbara coast.

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