« Shell turbinate, elevated-conical, turriform, moderately umbilicate, yellowish-fawn; apex slightly obtuse, smooth, with the top twisted, subperforate, spirally coiled; whorls 7, convex, separated from each other by a deep suture, transversely striated by packed cords alternately with larger ones […], elegantly granular, submoniliform; last whorl rounded, subinflated, a little depressed at the base; umbilicus mediocre, visible, circularly ridged above; aperture subcircular, effused, not pearly inside, with sharp margins joined with parietal callosity; columellar margin sinuous, reflexed, partially occulting the umbilicus. » – N. Tiberi: “Diagnose du nouveau genre méditerranéen Gyriscus”, Journal de Conchyliologie vol. 15, Paris 1867, p.303.

« The corneous rounded operculum is flat, almost fitting the shell aperture. Contrarily to most architectonicids’ opercula, the spirally arranged lamellae are not raised. In fact, these form a very distinctive sculpture, determined by a regular series of flattened callosities. » – Stanić & Schiaparelli: “New finding of living specimens of the rare architectonicid Heliacus (Gyriscus) jeffreysianus (Tiberi, 1867)”, Bolllettino Malacologico vol. 43 (9-121), p.144. The animal pictured below is one of these specimens discussed in the article.