This small cumacean lives in coral sand bottoms. Our specimens came from light traps, which caught them during their nightly swims into the overlying water. This may be Stephanomma goesii of Sars 1871, but seems to differ enough to be a new species. It occurs with and resembles the slightly larger Cyclaspis bicornis, but can be distinguished by having 5 instead of 4 pairs of legs, and smaller tubercles on the sides of the carapace. The genus was created for a single female specimen taken at St. Martin. Our specimens allow description of males for the genus, and reevaluation of its differences from the related Cyclaspis. Stephanomma goesii (the type and only species) has not been reported since, and has remained enigmatic. --Donald B. Cadien