Grapsoid crabs (Crustacea: Decapoda: Brachyura) new to the Sirte Basin, southern Mediterranean Sea—the roles of vessel traffic and climate change

Specimens of the grapsoid crabs Grapsus granulosus, Plagusia squamosa and Pachygrapsus transversus were recently collected in the Sirte Basin, on the southern rim of the Mediterranean Sea. The Erythrean alien G. granulosus is reported for the first time from the Mediterranean Sea, along with the second record in the Mediterranean of the Indo-Pacific P. squamosa, and the first record of P. transversus along the south-central Mediterranean coast. The relations between introduced grapsoid crabs, vessel traffic and climate change are dicussed.