Lacuna pallidula

Lacuna pallidula (da Costa, 1778) (Fig. 7D 1-D 3) Cochlea pallidula da Costa, 1778: 51, pl. 4, figs 4, 5. Lacuna pallidula – Harmer 1921: 665, pl. 53, fig. 25. — Fretter & Graham 1980: 250, figs 201-202. — Strand Petersen 2004: 29, fig. 7. — Moerdijk & Janse 2015: 23, fig. 11. MATERIAL AND DIMENSIONS. — Maximum height 4.7 mm, width 5.1 mm. RGM.1364981 (20), leg. ACJ; RGM.1365182 (1), leg. AWJ; RGM.1364913 (2), leg. WG; RGM.1365081 (51), leg. AWJ. SPECIES CHARACTERISATION. — Small, round shell. Three smooth teleoconch whorls; spire almost flat; last whorl 92% of the total height. Prosocline growthlines. Aperture round; moderately extent columella fold on an open umbilicus. DISTRIBUTION. — Lower Pleistocene: Scotland and Ireland (Harmer 1921); Atlantic, Selsoif, NW France (this paper). — Holocene: NSB (Strand Petersen 2004). Today this is predominantly a northern species extending from south of the Arctic Circle on the American coast from Greenland to Connecticut (Gould 1840; Trott 2004), in the eastern Atlantic the distribution extends from the White Sea (Vortsepneva et al. 2023), North Sea (Dumoulin 1989), British Isles (Fretter & Graham 1980; Guiry & Guiry 2011), France (Müller 2004) into northern Spain (Rolán 1983). The species is associated with Fucus serratus (Smith 1973).