Crustacea, Decapoda, Caridea, Alpheidae, Alpheus simus Guérin-Méneville, 1856: further report from Brazilian waters

The rock-boring snapping shrimp Alpheus simus Guerin-Meneville, 1856 is an inhabitant of shallow water reef habitats, from Florida and Yucatan throughout the West Indies (from Cuba to Barbados and Curacao) south to Brazil (Abrolhos Bank, Bahia) (Chace 1972; Christoffersen 1979). In this species, the rostrum is absent, a feature distinguishing it from all other Brazilian species of the genus Alpheus Fabricius, 1798. Moreover, the ocular hoods are rounded and unarmed, and the front is slightly emarginated between them (Chace 1972). Until now, A. simus was known from Brazil based on a single record by Christoffersen (1979). His material, referred to as Thunor rathbunae (Schmitt, 1924), was collected by R/V "Calypso" in 1961 (Sta. 85), between Santa Barbara Island and Siriba, Abrolhos Archipelago, Bahia, between 2-5 m, on sand and calcareous algae bottoms (Christoffersen 1979).