Acanthonyx formosa, a new species of spider crab (Decapoda, Brachyura, Majidae) from seaweed beds in Taiwan

Abstract

A new species of spider crab, Acanthonyx formosa, is described from seaweed beds in Taiwan. The species is allied to A. euryseroche Griffin and Tranter, 1986, from western Australia, but differs markedly in the proportions of the adult male rostrum, and in the structure of the hepatic tooth, the third maxilliped, the adult male chela, and the male first pleopod. Acanthonyx formosa is only the second species of Acanthonyx known from the Pacific, the other being A. simplex Dana, 1852, from Hawaii.