A new species of the alpheid shrimp genus Triacanthoneus Anker, 2010 (Crustacea: Alpheidae) from Belize

A new species of the alpheid shrimp genus Triacanthoneus Anker, 2010, is described based on material collected in a marine cave off Caye Chapel, Belize. Triacanthoneus chapelianus sp. nov. is the fifth species in the genus and can be distinguished from the other four species by the position of the dorsolateral teeth on the carapace, which in the new species have an anterior (= submarginal) position, and by the configuration of the posterior margin of the telson, with a notch in the middle portion and two pairs of spines and one pair of plumose setae. A key to the five species of Triacanthoneus is provided.