A REVISION OF THE AUSTRALIAN GENUS UMBILIA (GASTROPODA: CYPRAEIDAE)

Umbilia, an endemic Australian genus of cool-water cowry, comprises 11 species ranging in age from Late Oligocene to Recent, of which four species are known only in the living fauna. Fossil species occur in the Eucla, St Vincent, Murray, Otway, Bass and Gippsland Basins, and living species range from Western Australia to central Queensland. Species of the genus probably have no free-swimming larval stage, so that there is considerable morpho-logical variability which has led to the creation of many synonyms. Two subgenera are recog-nised here, Umbilia (Umbilia), with ten species, U. prosila sp. nov., U. leptorhyncha, U. petilirostris sp. nov., U. platyrhyncha, U. angustior, U. eximia ( = brevis, maccoyi, frank-stonensis, montismarthae and sphaerodoma), U. hesitata ( = beddomei, cera, howelli and tatei?), U. siphonata ( = breviplicata), U. armeniaca and U. capricornica, and U. (Pallio-cypraea) with one species, U.(P.) gastroplax. A possible ancestor of Umbilia, Palaeocypraea? eripnides, from the Upper Paleocene–Lower Eocene, of the Chatham Is, New Zealand, is newly described. Rhynchocypraea Cossmann, 1898 (type species Cypraea leptorhyncha McCoy) is synonymised with Umbilia