03 Myosotella myosotis apertural views. Salting on Severn Estuary, Gloucestershire, England. August 2011.

03 Myosotella myosotis apertural views. Salting on Severn Estuary, Gloucestershire, England. August 2011.

Two views of a 7.5 mm adult turned at different angles to show all features within palatal (outer) lip.
Single views of three juveniles, heights 5.8mm and 4.5mm.

Width 46% of height on adult and largest juvenile; 50% of height on two smaller juveniles.

Aperture on 7.5mm adult 54% of shell height; 58% on 5.8mm shell and 65% on 4.5mm shells.

1: sharp adapical angle of aperture.
2:parietal lip is a wide glazed area on the body whorl.

Juveniles (under 6.5mm high).
3:thin palatal (outer) lip lacks internal teeth and ridge.
4:columellar lip (lower part of inner lip) has two raised folds (partly concealed on some images as shell not tilted so as to show them).
5:parietal lip (upper part of inner lip) usually lacks a denticle.

Adults (over 6.5mm high).
6:palatal lip has internal pale calcareous ridge close to its rim.
7:single raised white denticle usually within the ridge.
8:columellar lip (lower part of inner lip) has two raised folds.
9:parietal lip (upper part of inner lip) often has a denticle.

Concise summary
juvenile: 2 protrubrances on inner lip. No ridge or denticle inside outer lip.
adult: 2, often 3, protrubrances on inner lip. Often a ridge, with or without single denticle, within aperture on outer lip.

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