Achatinella fuscobasis is a species of air-breathing land snail, a terrestrial pulmonate gastropod in the family Achatinellidae.

The color is glossy white with the last whorl yellowish and ornamented with a median zone and base of brown.

Their range is limited to around 100-250 square kilometers, with the majority being found on the leeward side of the Ko'olau Mountains.

[5] Achatinella's diet consists of microscopic colonies of black mold and fungi that are consumed using the snails radula.

Habitat destruction for agriculture and invasive species are noted as the biggest reason for population decline, though fires, collecting, drought, hurricanes, logging and human recreation are also to blame.