1: punctate spiral lines on white shell of 3 or fewer whorls.
2: earlier punctate spiral lines surviving on apex of older juvenile.
3: older juvenile has brown periostracum drawn out into row of subsutural hairs.
4: umbilicus-like slit in the apex caused by the change from the sinistral larval shell (protoconch) to a dextral later shell (teleoconch).

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