Patella ferruginea

Patella ferruginea Gmelin, 1791

Tunisia & Canale di Sicilia to Morocco; Sardinia and Corsica; Catalunya to Murcia. Some records from SE. France and Alborán. The species lives attached to rocks, often exposed to waves, mostly between the barnacle level and the corbellings of coralline algae (Lithophyllum). This thin layer of water is the most limited biotope of all mediterranean limpets. – Grazer. Due to overcollecting and destruction of habitat, the species is endangered everywhere. Synonyms: costoplicata, cypria, gorgonica, medusa, stella…

Surface water, on rock, la Guardiola, Cala d’Alivu, Isola Rossa, NW. Corsica. 24-54mm.

Patella ferruginea is protandrous, the animal becoming female when the size of its shell surpasses the 6cm. The species was abundant in western Mediterranean some millions years ago; used as food during the Neolithic, it disappeared almost completely during the XXth century AD (DORIS).

Same spot. Surface level, on a big rock. 53mm.

Like ferruginea, the epithet cypria may refer to the colour of this Athena’s shield (gorgonica, medusa), and not to Venus.
Other synonyms: lamarckii, rouxii.
On rock, Plage Oued Lau, Tanger, N. Morocco. 64mm.

The species in B. C. Payraudeau: Catalogue descriptif et méthodique des annelides et des mollusques de l’île de Corse, Paris 1826, plate VI – Patella Lamarckii.

« Testâ maximâ, ovali, laeviter depressâ; epiderme albido-fuscente; costis numerosis, compressis, ultrà periphoeriam prominentibus, alternatim parvis et majoribus; vertice subcentrali; intùs albâ; tres ad quatuor pollices longâ. »

The species in H. A. Pilsbry: Manual of conchology, structural and systematic vol. XIII, Philadelphia 1891, plate LIII.

« The strong rounded ribs, deeply crenulating the margin, distinguish this from other European species. The interior is faint bluish and slightly opalescent outside of the muscle-scar; inside of it there is a distinctly defined, opaque white callus. The ribs number from 44 to 50 in all. »

Patella cuprea in L. A. Reeve: Conchologia iconica vol. VIII, London 1855, plate VIII.

« A firm shell, of a semiglobose saucer-like form, rayed with crenuled ridges, alternately smaller, the exterior being of a semitransparent copper-brown white, the interior is bright silvery. »

A specimen crawling above the sea level, Islas Chafarinas (spanish sovereignty), north of Ras El Ma, Nador, NE. Morocco. Original picture provided by L. Sánchez Tocino (ES).
– (CC BY-NC-SA) –

Above and below: live specimens on their rocks, barnacle level, northern Alborán Sea.

Original pictures provided by B. J. Muñoz Sánchez (ES).
– (CC BY-NC-SA) –

Unusually tall specimen. Punta Revellata, in front of the Stazione di Ricerche Sottumarine è Uceanugrafiche di Calvi, NW. Corsica. Original picture provided by V. Moser for iNaturalist – (CC BY).