Cirsonella carinata (Hedley 1903)

Cirsonella carinata, common name the ridged false-top-shell, is a species of minute sea snail, a marine gastropod mollusk in the family Skeneidae.^[1]

Description

The height of the shell attains 1.7 mm, its diameter 1.8 mm. The minute, smooth and glossy, cream-colored shell has a turbinate shape. The four whorls have an impressed suture. The body whorl is bluntly keeled at the periphery. There is a sculpture of dense spiral microscopic striae. The base of the shell is rounded. The umbilicus is narrow and deep, and it is surrounded by a callus funicle which expands anteriorly to join the simple lip in an angular lobe. The aperture is subcircular.^[2]

Distribution

This marine species occurs off New South Wales, South Australia, Tasmania, Victoria, Australia, at depths between 73 m and 200 m.

References

• Cotton, B.C. 1959. South Australian Mollusca. Archaeogastropoda. Handbook of the Flora and Fauna of South Australia. Adelaide : South Australian Government Printer 449 pp
• Iredale, T. & McMichael, D.F. 1962. A reference list of the marine Mollusca of New South Wales. Memoirs of the Australian Museum 11: 1–109