Alvania dubiosa

Alvania dubiosa
	Shell of Alvania dubiosa (holotype)
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
Subclass:	Caenogastropoda
Order:	Littorinimorpha
Family:	Rissoidae
Genus:	Alvania
Species:	†A. dubiosa
Binomial name
	†Alvania dubiosa; Harmer, 1920

Alvania dubiosa is an extinct species of minute sea snail, a marine gastropod mollusc or micromollusk in the family Rissoidae.^[1]

Description

The length of the shell attains 3 mm, its diameter 2 mm.

(Original description) The minute, solid shell is ovate-conical. It contains 5 convex whorls. The body whorl is tumid and measures about two-thirds the total length. The three lower whorls are ornamented by well-marked longitudinal ribs, nearly straight, which die out or are cut off by strong spiral ridges, continuous to the base. The upper whorls are without sculpture. The spire is turreted, decreasing in size, compressed above, ending in a blunt rounded point. The suture is deep. The aperture is oval, rather short and expanded below. The outer and inner lip are thickened.^[2]

Distribution

Fossils of this species were found in late Pliocene strata at St. Erth, Cornwall, Great Britain.

References

^ MolluscaBase eds. (2024). MolluscaBase. Alvania dubiosa Harmer, 1920 †. Accessed through: World Register of Marine Species at: https://www.marinespecies.org/aphia.php?p=taxdetails&id=1027571 on 2024-02-06.5
^ Harmer F. W. (1920-1925). The Pliocene Mollusca of Great Britain, being supplementary to S.V. Wood's monograph of the Crag Mollusca. Vol. 2. Monographs of the Palaeontographical Society. 72(344): 485-652, pl. 45-52 (part 1, December 1920); 73(346): 653-704, pl. 53-56 (part 2, July 1921); 75(352): 705-856, pl. 57-64 (part 3, December 1923); 76(354): i-xiv, 857-900, pl. 65 (part 4, January 1925) This article incorporates text from this source, which is in the public domain.

This Rissoidae-related article is a stub. You can help Wikipedia by expanding it.

[WoRMS-1] MolluscaBase eds. (2024). MolluscaBase. Alvania dubiosa Harmer, 1920 †. Accessed through: World Register of Marine Species at: https://www.marinespecies.org/aphia.php?p=taxdetails&id=1027571 on 2024-02-06.5

[2] Harmer F. W. (1920-1925). The Pliocene Mollusca of Great Britain, being supplementary to S.V. Wood's monograph of the Crag Mollusca. Vol. 2. Monographs of the Palaeontographical Society. 72(344): 485-652, pl. 45-52 (part 1, December 1920); 73(346): 653-704, pl. 53-56 (part 2, July 1921); 75(352): 705-856, pl. 57-64 (part 3, December 1923); 76(354): i-xiv, 857-900, pl. 65 (part 4, January 1925) This article incorporates text from this source, which is in the public domain.

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