Patella vulgata Linnaeus, 1758

(Fig. 4B 1, B 2)

Patella rustica Linnaeus, 1758: 782 .

Patella vulgata – Harmer 1921: 780, pl. 62, figs 780, 781. — Wesselingh & Pouwer 2011: 129, fig. 1.

MATERIAL AND DIMENSIONS. — Maximum diameter 15.1 mm. — RGM.1310830 (1), leg AWJ; RGM.1315059 (1), leg AWJ .

SPECIES CHARACTERISATION. — Intermediate-high patelliform shell; apex placed two-thirds distance from anterior margin. Largest width at one-thirds distance from anterior margin. Sculpture of about 28 robust primary ribs that can develop slightly irregular knobs, with low secondary ribs and very fine but irregularly developed and spaced tertiary ribs. Edge coarsely wavy, corresponding mostly to primary ribs.

DISTRIBUTION. — Lower Pleistocene: Atlantic, Selsoif, France (this paper). — Upper Pleistocene: Channel region, Portland and Selsey (Harmer 1921). — Upper Pleistocene-Holocene: Netherlands (Wesselingh & Pouwer 2011). — Present-day: NE Atlantic coast from Norway to Gibraltar. Rarely reported from western Mediterranean.

REMARKS

As discussed above, identification of fresh Patellidae can be challenging, even more so for fossils, as characteristics such as colouration are generally not preserved. In this case, growth series of the four abundant NE Atlantic species were used for comparison. Most abundant is Patella rustica Linnaeus, 1758, which is characterised by a relatively flat shell with fine sculpture of alternating coarser and finer ribs, crossed by growth-lines forming an elongated reticulate sculpture. A few specimens represent Patella vulgata Linnaeus, 1758, at this locality characterised by a rugose sculpture, with more prominent and robust broad primary ribs that contain irregular knobs.