Apical Shell Sculpture of some African Freshwater Limpets (Mollusca: Basommatophora: Ancylidae)

Abstract

A Scanning Electron Microscope has been used to describe in detail the apical shell sculpture of sevenAfrican species (three genera) of freshwater limpet snails (Ancylidae). The apical sculpture of Ancylus fluviatilis (? syn. strigatus and ? brondeli) is striate, but quite different in basic pattern from the other three striate species studied, Ferrissia cawstoni, ‘Gundlachia’ burnupi and ‘G.’ I'hotelleriei. The apices of the last three are nearly identical, and most likely all three species are congeneric. The apical sculpturing of radiating punctae of the three species of Burnupia is quite distinct, not only from the striate Ancylus and Ferrissia, but also from the subapically pitted South American Uncaneylus.