Specimens of G. severnsi have been recovered from several of the Hawaiian volcanic islands, including Hawaiʻi, Maui, Oʻahu and Kauaʻi.

[1] Its range appears to have overlapped with that of the more coastal G. crinipes, a species which is widespread across the Indo-Pacific.

[1] This is also seen in the Ascension Island species Johngarthia lagostoma, where females are likely to die on their reproductive migration.

[1] It would have been an omnivore and a predator, possibly feeding on insects, land snails and bird's eggs.

[1] The specific epithet severnsi commemorates Mike Severns, the discoverer of the cave which housed most of the remains.