Occurence of the alien species Caprella scaura (Amphipoda: Caprellidae) in three Tyrrhenian lagoons

1 - Alien species represent a recognized worldwide threat to the integrity of the native communities, to the economy and even to human health; hence the understanding of invasive processes and their impact on the invaded ecosystems are essential to environmental conservation and management. 2 - In this paper we have reported, for some Italian lagoons, the first record of the alien species Caprella scaura Templeton, 1836, an amphipod species native to the Indian Ocean and now recorded worldwide. 3 - Specimens of C. scaura were collected in three Tyrrhenian lagoons (Santa Gilla, Caprolace and Fogliano), sorted into 5 categories (juveniles, males, immature females, mature females, breeding females) counted and measured for their total length. 4 - In Caprolace and Fogliano lagoons very few specimens were collected, while in the Santa Gilla samples a considerable number of individuals were found, particularly juveniles and immature females. 5 - Total length values of our specimens were lower than those reported from others Mediterranean areas. 6 - The introduction of this species in Caprolace and Fogliano lagoons is clearly a recent event while in Santa Gilla lagoon it is undefined