Role of ships' hull fouling and tropicalization process on European carcinofauna: new records in Galician waters (NW Spain)

Ten unusual decapod crustacean species are reported for the coasts of Galicia (NW Spain), eight of them recorded for the first time in this area. Three species: Pilumnopeus africanus, Charybdis hellerii and Pachygrapsus gracilis, are non-indigenous species. The reports of Panopeus africanus and Inachus aguiarii represent the northernmost localities of these African species, whose previous North limits were in the Southwestern European coasts. Remaining five species: Xaiva biguttata, Bathynectes longipes, Parthenopoides massena, Monodaeus couchii and Homola barbata are scarcely known species found within their distribution range. Updated data about these species are given, both from the point of view of their distribution and identification (morphological and molecular methods), as well as the potential pathways for introduction of the non-indigenous ones. According to evidence presented in the present study, biofouling still remains an important vector of species transmission and surely has been undervalued with respect to ballast water.