Brown Guard Crab

Trapezia digitalis

The Brown Guard Crab, known scientifically as Trapezia digitalis, is a small crustacean belonging to the family Trapeziidae. It inhabits the tropical and subtropical regions of the Indo-Pacific. Divers can find this species in benthic environments, typically at depths ranging from the surface to 26 meters. This depth range aligns with the majority of occurrence records, which show that 100% are found shallower than 40 meters and 90% are within 30 meters of the surface. The Brown Guard Crab is often associated with coral reefs, where it plays a role in the ecosystem as an epizoic species. Its mating behavior is characterized by a precopulatory courtship ritual, which involves olfactory and tactile cues, and usually involves indirect sperm transfer. As a member of the order Decapoda, it is mostly gonochoric, meaning individuals are distinctly male or female.