Achaeus is a genus of crabs comprising the following species: * Achaeus affinis Miers, 1884 * Achaeus akanensis Sakai, 1937 * Achaeus anauchen Buitendijk, 1939 * Achaeus barnardi Griffin, 1968 * Achaeus boninensis Miyake & Takeda, 1969 * Achaeus brevidactylus Sakai, 1938 * Achaeus brevifalcatus Rathbun, 1911 * Achaeus brevirostris (Haswell, 1879) * Achaeus brevis (Ortmann, 1894) * Achaeus buderes Manning & Holthuis, 1981 * Achaeus cadelli Alcock, 1896 * Achaeus cranchii Leach, 1817 * Achaeus curvirostris (A. Milne-Edwards, 1873) * Achaeus dubia Laurie, 1906 * Achaeus erythraeus Balss, 1929 * Achaeus foresti Monod, 1956 * Achaeus gracilis (Costa, 1839) * Achaeus inimicus Rathbun, 1911 * Achaeus japonicus (De Haan, 1839) * Achaeus kermadecensis Webber & Takeda, 2005 * Ac