Boucardicus must have microtunnels! Reassignment of three species into Acroptychia (Gastropoda: Caenogastropoda: Hainesiidae)

Boucardicus is a Madagascan endemic genus of the family Hainesiidae (subfamily Boucardicinae). The over 200 known species are variable in terms of shell shape, but their common trait is the presence of pre-constriction ribs, under which microtunnels run. Here we report three Boucardicus species without microtunnels, and as a consequence, transfer them to the genus Acroptychia as follows: Acroptychia boulangeri (Fischer-Piette, C.P. Blanc, F. Blanc & Salvat, 1993), Acroptychia (?) culminans (Fischer-Piette, C. P. Blanc, F. Blanc & F. Salvat, 1993) and Acroptychia (?) optio (Fischer-Piette, C. P. Blanc, F. Blanc & F. Salvat, 1993).

The variability of the genus Acroptychia is briefly discussed.