Molluscan alien species in Galicia: new records and new data

Although it is well known that Galicia has been a hotspot for the arrival of exotic marine mollusc species from other continents for decades, previously undetected new species continue to appear, associated with the bivalve aquaculture trade. While most of the species that have appeared are marine, freshwater and terrestrial species have also been found in recent years. Freshwater species all originate from the American continent and their arrival in our country seems to be linked to the aquarium trade. As for terrestrial species, although to a lesser extent, a potentially very dangerous pathway of introduction has been detected: the trade of ornamental plants, through which it is very easy to spread different species over a large area in a very short period, with the risk of future potential invaders. This paper addresses a total of 11 species, seven marine, three freshwater and one terrestrial. Our material of Ocinebrellus inornatus (Récluz, 1851), Ferrissia californica (Rowell, 1863), Succinea costaricana E. vonMartens, 1898 constitutes first record in Galicia. One species is tentatively identified as the West African Loripinus cf. senegalensis (Cosel, 2005) which would also be a first record, and Mercenaria mercenaria (Linnaeus, 1758) is confirmed as an established species in the northern Iberian Peninsula. For the remaining six species already known in our area, data are updated and additional information deemed of interest is included.