any marine snail of the family Volutidae (subclass Prosobranchia of the class Gastropoda). Most species have large, colourful shells, typically with an elongated aperture in the first whorl of the shell and a number of deep folds on the inner lip. Volutes are most common in warm, shallow waters but occur also in polar seas. Prized by collectors is the imperial volute (Aulica imperialis) of the Philippines; it is 25 cm (10 inches) long, with a spine-tipped body whorl finely checked with brown, and an outer lip that is wide and golden-lined.