Relevant Synonyms - Misidentification -  drawing : Tuvia Kurz

SHORT DESCRIPTION Carapace subobvate with sparse short hairs. One row of granules across the carapace at level of posterior antero-lateral spines and two transverse rows at protogastric region. Front straight, slightly notched, its margin transversely grooved. Antero-lateral margins with four teeth, posteriormost tooth smallest. Male abdomen with segments 3-5 fused. Chelipeds massive, unequal, chelae indistinctly costate above. Walking legs long and slender, somewhat hairy. color : brownish green, sometimes with darker spots on dorsal surface of carapace, paler ventrally. Fingers of chelae whitish. common size : CL 2.0 cm (max.). DISTINGUISHING CHARACTERISTICS Four antero-lateral teeth as opposed to five teeth in autochthonous xanthoids; frontal margin transversely grooved; fingers of chelae whitish, dark in Dyspanopeus sayi and all other Mediterranean xanthoid crabs. BIOLOGY / ECOLOGY Euryhaline species, found also in nearly fresh water. Breeding in late summer, egg bearing females from 0.6 cm CL. Egg diameter 0.3 mm. Omnivorous, feeding on leaf detritus as well as peracarid crustaceans. habitat : shallow enriched estuarine and brackish waters. On sandy muds with some kind of shelter (stones or oyster beds).

1st MEDITERRANEAN RECORD Italy, Northern Adriatic Sea, 1996 [1994]. DISTRIBUTION Worldwide : North-West Atlantic origin. Introduced to the Pacific coast of USA; Eastern Atlantic, from the Baltic Sea to Netherlands, France, Portugal and Spain; Black Sea, Caspian Sea. Mediterranean : recorded for the first time in Italy, Po River Delta, Adriatic Sea (Mizzan and Zanella, 1996 [1994]). Subsequently collected in Italy, Marano lagoon (Froglia, pers. comm., 1998), brackish habitats along the Romagna coast (Fabbri and Landi, 1999), and in France, Étang de Berre, near Marseilles (Noël, 2001). Noted in the Lake Tunis (Ben Souissi et al., 2004a; Ben Souissi et al., 2004b). ESTABLISHMENT SUCCESS Common in some brackish habitats along the Adriatic coast and near Marseilles. speculated reasons for success : - MODE OF INTRODUCTION Ballast transport or unintentional import with clam seed. IMPORTANCE TO HUMANS Extensively used in physiological studies, due to its tolerance to wide range of salinities and its abundance in the brackish habitats along the Atlantic coast of USA.

KEY REFERENCES Buitendijk A.M. and L.B. Holthuis, 1949. Note on the Zuiderzee crab Rhithropanopeus harrisii (Gould) subspecies tridentatus (Maitland). Zoologische Mededelingen, 30(7): 95-106. Eno N.C., R.A. Clark and W.G. Sanderson, 1997. Non-native marine species in British waters: a review and directory. Joint Nature Conservation Committee, Peterborough. 152 p. Mizzan L. and L. Zanella, 1996. First record of Rhithropanopeus harrisii (Gould, 1841) (Crustacea, Decapoda, Xanthidae) in the Italian waters. Bolletino del Museo civico di Storia naturale di Venezia, 46: 109-120.   Williams A.B., 1984. Shrimps, lobsters and crabs of the Atlantic coast of the Eastern United States, Maine to Florida. Smithsonian Institution Press, Washington, 550p. FEEDBACK / COMMENTS TO AUTHORS

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