« Shell very glossy, very smooth, very thin, purple and translucent […] Differs from the previous one [the nicaeensis sensu Risso, id est juvenile aperta according to Dolin & Ledon, 2002 p.341] by its shorter and wider canal, its colour constantly purplish, without apparent striae. Habitat: deep coralligen. » – A. Risso: Histoire naturelle des principales productions de l’Europe méridionale… vol. IV, Paris 1826, p.235.
 
« Shape fusiform, slightly elongated, equally narrowed on top and bottom; last whorl very tapered at the extremities, well rounded in the middle; aperture rather narrow, broadened at the base; labrum simple, barely thickened inside; columellar margin with an oblique fold at the top; channel short and wide; columella thickened, slightly arched; colour of a light red, peristome paler. » – A. Locard: “Les coquillles marines des côtes de France”, Annales de la Société Linnéenne de Lyon n.s. t.37, Lyon 1891, p.36.

« It differs from the previous species [the nicaeensis sensu Risso]: by its smaller size; by its globally more swollen curve; by its shorter and more dilated canal; by his test striped only at the extremities; by its purple colouration, etc. » – Locard & Caziot: “Les coquillles marines des côtes de Corse”, Annales de la Société Linnéenne de Lyon n.s. t.46, Lyon 1899, p.219.

Jeffreys (British Conchology vol.5 p.222) considers Ovula purpurea as a junior synonym of Ovula patula Pennant. Monterosato (Notizie intorno alle conchiglie mediterranee p.54) considers also purpurea as a variant of patula. But purpurea has a constant purplish colour and a narrower shape.