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Diagnosis

Distinguished from other BC snails of similar size by the combination of its rather brightly pigmented, frequently banded shell, having a purplish brown apertural lip and no umbilicus.

Shell

Medium-sized (maximum mature shell width, 20–25 mm); growth determinate; globose-heliciform; opaque. Whorls: ca 4½–5¼; regularly increasing in width but sometimes final portion of the last whorl a bit more rapidly expanded; spire whorls convex. Spire: low conic-domed; apex bluntly rounded. Suture: moderately impressed. Last whorl: descending at the aperture; constriction of whorl behind the palatal lip very slight; no apparent crest. Periphery: rounded, medial on the last whorl. Protoconch: smooth. Teleoconch sculpture: irregular, low, rounded wrinkle-like colabral riblets; and sparse, shallow malleation. Periostracum: varnish-like. Umbilicus: sealed by the baso-columellar lip. Aperture: rounded, height about equal to width. Peristome: incomplete. Apertural dentition: none. Palatal and baso-columellar lip: rather thick, straightened (in apertural view); appressed to the body whorl, not projecting. Peristome, viewed from side: prosocline, slightly arched. Parietal callus: glazed, transparent, inconspicuous or purplish brown. Colour (including periostracum): straw yellow, orange or brown, with 1–5 dark black-brown or chestnut brown spiral bands that may be fused together or entirely absent; frequently with darker colabral streaks at irregular intervals; shining; aperture showing bands within; lip generally purple-brown or sometimes paler, pinkish.