Gibbula albida (Gmelin, 1791)
nature22.com/estran22/mollusques/gasteropodes/gasteropode…
Opaque white shell, sometimes with brownish or dark reddish marks. Maximum diameter 25 mm.
Stepped shell-profile.
Umbilicus is absent or very small with comma-shaped groove leading into it.
Soft parts resemble G. magus; snout has transverse brown lines; generally less colourful than G. magus.
Black eye in blue area on peduncle tip.
Mediterranean species with established populations in Galicia and Brittany; probably introduced with oysters transplanted from Italy (Trigo et al. 2018). Not Britain