The marine biota of the southwestern coast of Turkey was studied by diving between 1996 and 2003. Nine alien decapod crustaceans of Red Sea origin have been noted. Four constitute new records for Turkey, for three we report significant range extensions within Turkey, and a new species of the widely distributed Indo-Pacific palaemonid genus Urocaridella Borradaile, 1915, is described, while the genus is reported for the first time from the Mediterranean. The main morphological characters used for differentiating Urocaridella pulchella n. sp. are the number and disposition of the rostral spines, the carpal/palmar length ratios of the first and second pereopods, the propodal/dactylar length ratios of the last three pereopods, the presence and shape of a dorsal ridge on the third abdominal segment, and the shape of the fifth pleuron.
Crustacea, Decapoda, Palaemonidae, Urocaridella, Mediterranean, Turkey, alien species, new species.