CORAMBE-BATAVA KERBERT, 1886 (GASTROPODA, OPISTHOBRANCHIA), AN IMMIGRANT IN THE NETHERLANDS, WITH A REVISION OF THE FAMILY CORAMBIDAE

The nudibranch mollusc Corambe batava Kerbert, 1886, was at that time considered to be endemic to the brackish Zuiderzee in The Netherlands. It has recently been observed in France and is apparently an immigran t originating from the east coast of North America. The species is fou nd conspecific with C. obscura (Verrill, 1870), which name has priorit y. It is one of the many successful immigrants which have a preference for brackish habitats. The original description of the type-species C . sargassicola Bergh, 1871 of the genus Corambe Bergh, 1869 is not ent irely clear and this has confused the taxonomy of the genera. We re-ex amined the type specimen which appeared to have no natural notch in. n otum and foot, thus the described incisions should be considered as ar tefacts. Therefore, Corambe is the same as Doridella Verrill, 1870. Ba sed on three distinguishing characteristics in all described Corambida e, this family falls into three genera: Corambe Bergh, 1869 (including Doridella Verrill, 1870, and p.p. Corambella Balch, 1899), Neocorambe nov. gen. (including p.p. Corambe), and Paracorambe nov. gen. (includ ing p.p. Corambella).