Sathrochthonius insulanus is a species of pseudoscorpion in the Chthoniidae family. It is endemic to Australia. It was described in 1976 by Austrian arachnologist Max Beier.
The body length is 1.0-1.2 mm. The colour is pale yellowish-brown.
The species occurs on Lord Howe Island, an offshore island of New South Wales in the Tasman Sea. The type locality is plant litter on Lord Howe.
The arachnids are terrestrial predators.