The Gammarus pulex-group in Italy (Crustacea, Amphipoda) (A study based on material from the Museo Civico di Storia Naturale, Verona)

A historical review is given of the literature oil Italian members of the genus Gammarus. Only three Gammarus species were known with certainty from Italy, viz G. fossarum Koch, 1836, G. lacustris G.O. Sars, 1863, and G. cf. balcanicus Schäferna, 1922. G. fossarum is widely distributed in the northern part of Italy. Near the Yugoslavian border a member of the G. balcanicus-group sometimes coexists with this species. G. lacustris seems to be confined to mountain lakes. Some doubt remains about the identity of G. fontinalis A. Costa, 1883. During the present study a new species was found, G. italicus, inhabiting a restricted area in the central part of Italy and the northwestern part of Sardinia.