Eight spiral bands on and above periphery of body whorl. Earlier whorls have six, five bands and four bands.
Peripheral band larger than other bands on body whorl. Suprasutural (wide) bands of other whorls were peripheral when previously they each in turn were the body-whorl.
Grooves below periphery do not persist onto earlier whorls as become hidden as shell grows.
Very fine transverse striae visible on smooth peripheral band. Thin yellow-brown periostracum visible on narrow bands; lost from peripheral/suprasutural bands.
Height 23 mm Portland Harbour. April 2012.