The apical protoconch is the same size at all post-larval stages of growth, but is largest relative to shell size, and liable to least erosion, on small juveniles such as this. It is smooth and white with a little more than 2 whorls in Ria de Vigo (Rolan & Luque, 1994), but see 09Tr .
Shell height 5.6 mm. West Anglesey, Wales, May, 2016.

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