Remnants of dark periostracum in suture (1) and on base (2). Faint wrinkles running into umbilicus (3). Single, subsutural, spiral line of purplish marks (4); hidden on body whorl by periostracum (1). Spire profile stepped (5).
Shell height 26 mm. Sublittoral, Llŷn Peninsula, Wales. September 2015. Leg. P. Brazier.