Apical protoconch on beached, 9 mm high shell.
1: first whorl of smooth, unsculptured protoconch,
2: second, incomplete, whorl of protoconch.
T: sculptured teleoconch,
>: transition line between protoconch and teleoconch.
Complete shell shown at 41Tr 41 Tritia reticulata growth stages. Beached shells. Lower shore has sand with Zostera. Llŷn, Wales. August 1968. .
Rolan & Luque (1994) state that in the Ria de Vigo the protoconch is a little more than 2 turns on T. reticulata, and a little less than 2 turns on T. nitida. But this does not apply to this Welsh specimen of T. reticulata which has a protoconch of c. 1.8 turns. It would be advisable not to use this feature for differentiating the two species in areas beyond Ria de Vigo.
Llŷn, North Wales. August, 1968.

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