Long confused with some forms of Rissoa similis Scacchi. « Shape distinctive, conical, tawny or chestnut-coloured, with a dull apex, the first whorls sub-coiled, the last one mostly devoid of ribs and spirally streaked towards the base; aperture round, purplish. » – T. A. di Monterosato: “Conchiglie littorali mediterranee”, Il Naturalista siciliano vol. III, Palermo 1883-1884, p.139. Some shells can bear axial costae (14 in number), separated from each other by narrower interspaces; some shell, such as the one pictured here, are devoid of axials; and all intergrades exist. But a constant feature is the spiral sculpture that covers all the surface of the late part of the teleoconch. « Last whorl usually devoid of costae. No labral thickening. […] Peristome edged in purple. Inside of the aperture white. Operculum thin, horny, paucispiral. » – Bucquoy, Dautzenberg & Dollfus: Les mollusques marins du Roussillon vol. I, Paris 1884, p.267.