« Shell […] much flatter than the Anatina convexa, rough, striate transversely, brownish white. Beaks nearly central, with the points not opposite, but crossing each other at the tips. Teeth projecting and running obliquely to the anterior side, with a cavity or notch behind a small erect denticle. Inside with an oblique rib from the tooth towards the truncated end. […] This has the teeth oblique, etc… »

The shell differs from that of corbuloidea by the keels on the valves: one apico-rostral in pubescens, but two in corbuloidea – the apico-rostral and an apico-basal. The keel of pubescens differs from that of convexa in being sharper, while it is very blunt in convexa. Finally, phaseolina has a more lengthened shell, with an apico-rostral keel which is intermediate between the sharp one of pubescens and the rounded one of convexa.