New shallow-water nudibranch records (Mollusca: Gastropoda: Heterobranchia) from North West Atlantic coast of Iberian Peninsula

Samplings carried out in the last years by the "Grupo de Estudo do Medio Marino" (GEMM) in Ria de Arousa, have resulted in the discovery of four species never recorded before in the Iberian Peninsula waters. New data on the feeding habits of Atagema gibba Pruvot-Fol, 1951, Onchidoris bilamellata (Linn, 1767) and Armina neapolitana (Delle Chiaje, 1824) are given, as well as details about the number of specimens observed and reproductive behavior, which leads us to assume the presence of stable populations of these species in the area. Flabellina affinis (Gmelin, 1791) was previously reported for Galician waters, but according to the published image, this seems to have been misidentified with F. ischitana Hirano & Thompson, 1990. We present here new data about the presence of large numbers of this southern species in the area.