Cirsonella extrema
species of mollusc
Cirsonella extrema is a species of sea snail, a marine gastropod mollusk in the family Skeneidae.
Description
The height of the yellowish white shell attains 2.7 mm, its diameter 2.9 mm. The spire contains 3½ whorls. The round aperture is somewhat oblique. The peristome has a thickened callus, expanded on the left side. Its top is attached to the penultimate whorl. it covers mostly the umbilicus. The brownish operculum is rather thick and consists of polygyrous spirals.
Distribution
This marine species occurs in Antarctic Ocean waters off the South Shetland Islands at depths between 311 m and 426 m.
References
Engl W. (2012) Shells of Antarctica.
“Cirsonella extrema” enters the record as species of mollusc. Crown Archives preserves that source wording while asking what Cirsonella, extrema and species can confirm, complicate or overturn.
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“Cirsonella extrema” is worth following because a concise public description often conceals a longer documentary argument. Here, Cirsonella, extrema and species provides the most credible route into that argument.
Datasets, specimens, observations and peer-reviewed methods provide the appropriate test for the technical claims summarized here. The source revision retrieved here is dated Jun 5, 2026. The linked authority identifier is Q5122082. None of the 0 selected statements returned an explicit reference. The first chronological checks are 2012.
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This entry incorporates text from “Cirsonella extrema” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.