Caecum digitulum
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Caecum digitulum | ||||||||||||||
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Scientific classification | ||||||||||||||
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Binomial name | ||||||||||||||
Caecum digitulum Hedley, 1904 |
Caecum digitulum is a species of minute sea snail, a marine gastropod mollusc or micromollusk in the family Caecidae.
Contents |
[edit] Distribution
This species is endemic to New Zealand including the Chatham Islands and The Snares.
[edit] Habitat
They are found alive under stones in the upper tidal zone. Empty shells are dredged commonly to a depth of at least 90 m, and the coiled embryos seem to occur only in the dredgings.
[edit] Shell description
The shells have discoidal nuclear whorls that are shed soon after the adult stage commences. The shell in the adult stage is in the form of a simple slightly curved tube, now sealed off at the narrow end by a blunt rounded septum. The embryonic shell has 2½ smooth whorls, and the adult shell has the simple curved tube, pale brownish in life. The aperture is circular and so is the tight fitting operculum.
The shell height is up to 2.3 mm, and the width is up to 0.5 mm.
[edit] Life habits
The animal grazes upon filmy organic deposits, and moves about jerkily by advancing the foot and then dragging the shell in a series of short steps.
[edit] References
- Powell A. W. B., New Zealand Mollusca, William Collins Publishers Ltd, Auckland, New Zealand 1979 ISBN 0-00-216906-1