Thoristella chathamensis cookiana
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| Thoristella chathamensis cookiana | ||||||||||||||||||||
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| Thoristella chathamensis cookiana Powell, 1934 |
Thoristella chathamensis cookiana is a subspecies of very small sea snail, a marine gastropod mollusc in the family Trochidae, the top snails or top shell.
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[edit] Distribution
This subspecies is endemic to New Zealand, around the south of the North Island and the north of the South Island.
[edit] Habitat
These top snails are found under rocks at low tide.
[edit] Shell description
The shell is of light build, with a low, broadly convex spire, obsolete shoulder, and no peripheral flange. The shell sculpture consists of numerous fine regular spiral cords, about 7 on the penultimate, and 29 on the body whorl and base.
The shell coloration is greenish-buff, the upper surface with radial dark grey maculations, and the base with the spiral cords either lined continuously, or intermittently, with dark grey.
The shell height is up to 4 mm, and width up to 6 mm.
[edit] References
- Powell A. W. B., New Zealand Mollusca, William Collins Publishers Ltd, Auckland, New Zealand 1979 ISBN 0-00-216906-1
