Trivia juveniles.
Maximum length when live 13 mm, excluding protruding foot and tentacles.
1: mantle lobes not fused; often withdrawn to expose juvenile white shell.
2: if mantle lobes fully expanded, a dorsal break line is present, but not always visible.
3: dorsal surface of mantle lobes often with stalk-like papillae that may branch terminally.
4: mantle lobes dorsally whitish or pale yellowish; developing dark bands and/or marks as Trivia matures.
5: live animal is spheroid with a respiratory siphon.
October 2014, Dorset © J. Chamberlain, and
August 2011, Cornwall, England © N. Ward.

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