First records of the crayfish Procambarus clarkii (Girard, 1852) (Decapoda, Cambaridae) in Lake Varano and in the Salento Peninsula (Puglia region, SE Italy), with review of the current status in southern Italy

The occurrence of the red swamp crayfish Procambarus clarkii is documented in the surroundings of Lake Varano (Puglia region, SE Italy), testifying to the ongoing diffusion of this invasive crayfish in north-eastern Puglia, an area characterised by an extensive network of natural and artificial watercourses. In addition, the species is recorded for the first time in the Salento Peninsula, in the south-western part of the region. The hydrology of the area is dominated by karstic phenomena, and the ecological consequences of the colonization of hypogean environments by P. clarkii are discussed. These records, in conjunction with a number of recent observations made in Puglia and in other regions of southern Italy including Sicily and Sardinia, indicate that the species is far more widespread in the area than previous studies have suggested.