Relevant Synonyms - Misidentification -  photo : Ch. Schubart

SHORT DESCRIPTION Carapace quadrilateral, naked; lateral margins arched, tridentate, posterior tooth smallest. Front half as wide as carapace, sinuous. Sub-orbital stridulating organ a finely striated crest. Chelipeds of male with membranous swelling at the base of the movable finger, carpus with robust spine on inner anterior margin. Dactyls of walking legs shorter than propodi, meri with subdistal spine on anterior margin. color : carapace mottled greenish-brown, small reddish spots on the upper parts of the chelipeds, banded walking legs. common size : CL 3 cm. DISTINGUISHING CHARACTERISTICS Membranous swelling between fingers of male cheliped. Dactyls of walking legs shorter than propodi. Carpus of chelipeds with robust spine on inner anterior margin. BIOLOGY / ECOLOGY Primarily herbivorous diet, possibly omnivorous. In the western Atlantic the crab reproduces from late April through September, fecund: over 40,000 eggs in a brood, several broods per year. Zoeal larvae are tolerant of a wide range of temperature/salinity combinations. habitat : rocky intertidal.

1st MEDITERRANEAN RECORD Croatia, northern Adriatic Sea, 2002 [2001]. DISTRIBUTION Worldwide : Western Pacific, from Sakhalin to Hong Kong and Japan. A single specimen was found in New Jersey, USA in 1988, but has since spread from Massachusetts to North Carolina. Recently reported from Le Havre, France and the Netherlands. Mediterranean : a single specimen from Croatia, western Istra, northern Adriatic (Schubart, 2002 [2001]). Found in the Lake Tunis and the Port of Radès (Ben Souissi et al., 2004b). ESTABLISHMENT SUCCESS None, but potentially present. speculated reasons for success : - MODE OF INTRODUCTION Probably in ballast. IMPORTANCE TO HUMANS None.

KEY REFERENCES Ben Souissi J., J. Zaouali, M. Rezig, M.N. Bradaï, J.P. Quignard and B. Rudman, 2004b. Contribution à l'étude de quelques récentes migrations d'espèces exotiques dans les eaux tunisiennes. Rapp. Comm. Int. Mer Médit., 37: 302. Breton G., M. Faasse, P. Noël and T. Vincent, 2002. A new alien crab in Europe: Hemigrapsus sanguineus (Decapoda: Brachyura: Grapsidae). Journal of Crustacean Biology, 22(1): 184-189. McDermott J.J., 1998. The western Pacific brachyuran Hemigrapsus sanguineus (Grapsidae) in its new habitat along the Atlantic coast of the United States: geographic distribution and ecology. ICES journal of Marine Science, 55(2): 289-298.   Sakai T., 1976. Crabs of Japan and the adjacent Seas. 3 Vols. Kodansha Ltd. Tokyo, 1-773, pls 1-251. Schubart Ch. D., 2003. The East Asian shore crab Hemigrapsus sanguineus (Brachyura: Varunidae) in the Mediterranean Sea: an independent human-mediated introduction. Scientia Marina, 67(2): 195-200. FEEDBACK / COMMENTS TO AUTHORS

Last update of the species sheet: February 2005 ©ciesm 2002