Geosesarma spectrum, a new species of semiterrestrial vampire crab (Crustacea: Decapoda: Brachyura: Sesarmidae) from Brunei Darussalam, Borneo.

A new semiterrestrial vampire crab from the family Sesarmidae, Geosesarma spectrum n. sp., is described from Brunei Darussalam (Borneo). The new species is characterised by its colouration in life, relatively large size, and form of the carapace, ambulatory legs and gonopods. The new species is compared to its closest congeners from Borneo. This description brings the number of Geosesarma species to 60.