THE RISSOININAE (GASTROPODA, RISSOIDAE) OF THE PITCAIRN-ISLANDS, WITHTHE DESCRIPTION OF 2 NEW SPECIES

This paper reviews the Rissoininae from the four islands that comprise the Pitcairn Group. The material was collected during the Sir Peter S cott Commemorative Expedition to the Pitcairn Islands between October and December 1991. Twelve species belonging to this subfamily are repo rted, including two undescribed taxa. The well-known species are liste d with synonymies and the poorly known species are (re)described and i llustrated. The shells of two new species, Rissoina (Rissoina) fraterc ula and Rissoina (Rissoina) schubelae, are described in detail. The bi ogeographical relationships of the fauna are briefly discussed.