Diagnosis: Radula with well-developed, transversely elongate latero-marginal plates; cusps of rachidian and inner laterals triangular, longitudinally elongate and relatively finely toothed. Shell generally turbiniform with rounded often shouldered whorls; sculpture of spiral cords, spiral lirae or both, commonly with axial pliculae, particularly below suture. Epipodial fold with flap-like extension between first and second epipodial tentacles; epipodial tentacles generally three on each side.
Description: Shell low to high turbiniform, whorls rounded often with a tabulate shoulder, periphery at or near mid-whorl; teleoconch of up to 6 whorls; species with a large protoconch (greater than 600 µm in diameter) generally have one less whorl than those with a small protoconch. Sculpture of spiral cords, spiral lirae, or both, with axial pliculae developed to a variable extent. Umbilicus deep, open to apex, varying in width and often, but not always, bordered by a strong spiral cord. Aperture circular to subcircular, peristome complete or nearly so; interior nacreous; external cords when present crenulate outer lip and appear as grooves in interior nacre.
Protoconch: Solarielline, but very variable in diameter 350-800 µm, consisting of approximately H whorls; sometimes distinctly globose. Colour: Variable, some monochrome, others spotted, mottled or axially striped; colour pattern characteristic for some species, not so for others; some normally patterned species also occur in a non-patterned, monochrome form; many with a pink/green iridescence when fresh. Dimensions: Moderate to small for subfamily, few exceeding 12 mm in diameter.
Radula: Radula short, broad with ca 20 rows of teeth, rows with a distinct posterior dip in mid-line and marginally, giving a flattened M-shape; formula (6-10) + 1 + 4 + 1 + 4 + 1 + (6-10). Rachidian and inner two laterals triangular, longitudinally elongate and relatively finely toothed; third lateral often somewhat elongate, usually with a reduced cutting edge; fourth lateral long, scythe-shaped to spatulate, finely toothed distally on one or both sides; bases of laterals not or only weakly interlocking. Latero-marginal plates well developed, rectangular, transversely elongate; interspecifically variable in length; set at a distinct angle to transverse axis; outer end with a U-shaped notch into which fits base of first marginal. Marginals few, usually less than ten, elongate, curved, evenly tapering, rarely if ever denticulate.
Southern African species, though very similar to type species, generally have more elongate, narrower rachidians and laterals.