Steromphala cineraria (Linnaeus 1758)

Steromphala cineraria is a species of small sea snail, a marine gastropod mollusc in the family Trochidae, the top snails.^[1]

Description

The size of the shell varies between 12 mm and 18 mm. The thick, narrowly umbilicate, rarely imperforate shell has a conical, thick shape. It is cinereous, densely marked with numerous narrow longitudinal brown or reddish lines, or broader stripes. The 6 whorls are flattened, with 7 or 8 thread-like spiral ridges on the upper surface of the body whorl, with often one or two finer striae between each ridge, and about a dozen fine ridge-like striae on the under side. The body whorl is angulate at the periphery, somewhat convex beneath. The aperture is subrhomboidal and smooth within. The columella is straightened in the middle. The umbilicus is narrow.^[2]

Distribution

This species occurs in the North Sea, the Mediterranean Sea, and in the Atlantic Ocean (Azores, Canary Islands, Morocco).

References

• Lowe, R. T. (1861). A list of shells observed or collected at Mogador and in its immediate environs, during a few days' visit to the place, in April 1859. i>Proceedings of the Zoological Society of London. 1860: 169-204
• Backeljau, T. (1986). Lijst van de recente mariene mollusken van België [List of the recent marine molluscs of Belgium]. Koninklijk Belgisch Instituut voor Natuurwetenschappen: Brussels, Belgium. 106 pp.
• Gofas, S.; Le Renard, J.; Bouchet, P. (2001). Mollusca, in: Costello, M.J. et al. (Ed.) (2001). European register of marine species: a check-list of the marine species in Europe and a bibliography of guides to their identification. Collection Patrimoines Naturels, 50: pp. 180–213
• Muller, Y. (2004). Faune et flore du littoral du Nord, du Pas-de-Calais et de la Belgique: inventaire. [Coastal fauna and flora of the Nord, Pas-de-Calais and Belgium: inventory]. Commission Régionale de Biologie Région Nord Pas-de-Calais: France. 307 pp.