On the occurrence of the invasive Atlantic blue crab Callinectes sapidus Rathbun 1896 (Decapoda: Brachyura: Portunidae) in Sicilian inland waters

The Atlantic blue crab Callinectes sapidus Rathbun, 1896 is included among the worst invasive alien species in the Mediterranean Sea. Here, we report the finding of the species in two Sicilian rivers, the Irminio and the Imera Meridionale, where it was collected up to 6 km from the river mouths. Although several records of the species are already available from Italy, this is the first evidence of the occurrence of this invasive crab so far from the coastline in the whole country. In the light of the well-known impact of the Atlantic blue crab on the invaded water bodies, the monitoring of the species and appropriate mitigation strategies should be implemented in order to protect the threatened native biota of Sicilian inland waters.