Image and text adapted from Alder (1844); only a small minority display all the features. Upper whorls smooth (1). About 30 very delicate faint costae (2) crossed basally by few faint spiral striae (3). Columella straight (4), angulated at base (5). Inner lip scarcely reflected with slight depression behind (6). Dark purple or black margined opercular lobes (7), dorsolateral line (8) and peripheral line on foot (9).