First report of the brown shrimp Penaeus aztecus Ives, 1891 (Crustacea, Decapoda, Penaeidae) in the Tyrrhenian Sea

Two specimens of the penaeid shrimp Penaeus aztecus, a West Atlantic species, were collected off Castiglione della Pescaia, Tyrrhenian coast of Italy. The species identity was confirmed based on morphological characters and by sequencing 510 nucleotides of the mtDNA 16sRNA gene. This alien species has been previously recorded off Turkey, Greece and Montenegro.