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Genus Bullinularia

Shell is ovoid or circular in front view, hemispherical with flattened ventral surface in lateral view; covered by small mineral particles in sheet-like organic cement, smooth, dark brown and opaque. Aperture is eccentric, invaginated, completely or partially hidden by the dorsal apertural lip (cryptostome). A key character is the pores on the dorsal lip, on the apex and, depending on the species, on the ventral side. Ecology: soils, mosses. Type species: Bullinularia indica (Penard, 1907)