On the true identity of Sphaerium borneense Sowerby

Although our knowledge of the non-marine mollusc fauna of Borneo must be very incomplete, it is certain that this huge island supports an immensely rich and varied fauna. It is equally certain that even without the additions that will be made eventually, the existing record is in need of considerable revision; undoubtedly a number of species will have to fall into synonymy or be expunged from the list. The subject of this note is to be synonymised and probably expunged. Sphaerium borneense Sowerby, was described and figured from material in the British Museum (SOWERBY, 1878b, Pl. 15 Sp. 42), with ‘Borneo’ as the locality. ODHNER (1940, p. 115) notes that it has not been refound, and on the basis of SOWERBY’S poor figure suggests that it may belong to the genus Byssanodonta, When one considers the known recent distribution of Byssanodonta (Central and South America, Trinidad; Africa, Madagascar and Mauritius) the presence of this genus in Borneo would be of considerable interest. PRASHAD (1921, p. 505) uses this same figure for comparison purposes when describing Sphaerium cecilae from the adjacent island of Sumatra. An inspection of the original material reveals that this species is not referable to either Sphaerium or Byssanodonta.