The identity of Euchirograpsus polyodous (Stebbing, 1921) (Decapoda, Brachyura, Plagusiidae), with a key to the genus

Abstract

Abstract The identity of the poorly known plagusiid crab Euchirograpsus polyodous (Stebbing, 1921) is clarified on the basis of a good series of specimens from Zanzibar. The species proves to be a senior synonym of Euchirograpsus madagascariensis Türkay, 1978. The species is characterized by the more elongate and rugose third maxillipeds, distinctly serrate flexor margins of the second and third ambulatory legs, presence of only five major pairs of corneous setae on the ambulatory dactylus, and structure of the male first gonopod. The holotype of Euchirograpsus madagascariensis Türkay, 1978, is here designated as the neotype of Pachygrapsus polyodous Stebbing, 1921, making both names objective synonyms. A key to the nine species of Euchirograpsus is provided.