Gyriscus asteleformis: Difference between revisions

Gyriscus asteleformis is a species of sea snail, a marine gastropod mollusk in the family Architectonicidae, known as the staircase shells or sundials.

This species is endemic to New Zealand, found between the northern tip of the North Island and the Three Kings Islands.

This species is found at depths of about 90 m.

The shell of this species is small, trochiform, with a rounded body whorl, spiral granose sculpture, a narrow umbilicus, and a distinctive operculum that is flat, multispiral, circular, with a central nucleus. The protoconch is large, smooth and almost completely inverted, the umbilicus showing as an apical pit. Adult sculpture is of linear-spaced finely gemmulate spiral cords.

Coloration is a uniform buff.

Height is up to 8 mm, and width is up to 7.5 mm.

• Powell A. W. B., New Zealand Mollusca, William Collins Publishers Ltd, Auckland, New Zealand 1979 ISBN 0-00-216906-1
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