Shell similar to Architectonica but smaller, of conical shape, and lacking axial sculpture, apart from crenulations around the umbilicus. Operculum circular, flat to concave, multispiral, with a subcentral nucleus.

Teleoconch: shell medium-sized (approximately 10 mm), roundly cone-shaped with narrow umbilicus (ca. 14 % of shell diameter); whorls bulging; upper (apical) side usually completely smooth, rarely with weak spiral striae; early posdarval shell sometimes with ± weak nodular sculpture; in Recent species upper peripheral rib completely reduced, therefore shell periphery formed by two ribs (LPR and less prominent IPR); upper point of whorl attachment at or below LPR; base smooth except for nodose rib surrounding umbilicus (UC); umbilical wall without spiral ribs; uniformly yellowish to dark brown, with regular fleck pattern on peripheral ribs, surrounding umbilicus (UC) always light Protoconch: small to medium-sized (ca. 0.7-1.0), distincdy heterostrophic, callous with distinct, short anal keel. Radula: five-toothed taenioglossate; rachidian with narrow central cusp flanked on either side by an equally strong, filiform cusp (P. lutea). Operculum: horny, circular with broad last whorl, flat with mushroom-shaped, peg-like projection on body side; peg with grooves arranged in clockwise fashion.