Primera cita de Mitrella psilla (Duclos, 1864) (Gastropoda: Columbellidae) en España (Marina de Valencia, Mediterráneo Occidental)

In this work is reported for the first time the presence of an established population of the gastropod Mitrella psilla (Duclos, 1864), native to the coasts of West Africa, in Spain (Marina of Valencia, Western Mediterranean). This record extends the range of distribution of this species in the Mediterranean, known to date only from the ports of La Goulette (Gulf of Tunisia) and Civitavecchia (Tyrrhenian Sea, Italy). The specimens were located in shallow biological concretions (0-3 m) attached to artificial substrates (pontoons, internal walls, artificial reefs and breakwaters). Only specimens were found in summer, both in extra and intraport stations and both adults and juveniles. The species, with a tropical Atlantic origin (from Mauritania to Angola), however, is not found in the Strait of Gibraltar or the Alboran Sea and, probably, has been introduced by maritime traffic through the transport of adults / juveniles or by drifting egg capsules (not by ballast water since it lacks pelagic larval phase). Its presence increases the number of NIS gastropod species in Spanish waters to 39