« Shell minute to very large, white, uniformly colored, or patterned; protoconch paucispiral; lip thickened, smooth or denticulate; external varix present or absent; siphonal notch present or absent; columella with 2-6 plications; internal whorls unmodified type. » – Coovert & Coovert: “Revision of the supraspecific classification of marginelliform gastropods”, The Nautilus vol.109(2-3), Melbourne (Fla) 1995, p.75.
 

« Shell small to moderately large, color translucent white, amber, or brown, usually with darker bands; spire immersed, or low to tall; lip thickened, smooth, not denticulate; external varix usually absent, but weak to strong in some species; siphonal notch absent or weak; columella with 3 or 4 plications, some species with weaker 5th or 6th, combined occupying half or less of the aperture. » – Coovert & Coovert: op. cit. p.90.