Vertigo modesta (Say 1824)

Vertigo modesta, common name the cross vertigo, is a species of minute air-breathing land snail, a terrestrial pulmonate gastropod mollusk or micromollusk in the family Vertiginidae, the whorl snails. ^[1]

Subspecies

• Vertigo modesta castanea Pilsbry & Vanatta, 1900
• Vertigo modesta concinnula Cockerell, 1897
• Vertigo modesta modesta (Say, 1824)

Description

(Described as Isthmia corpulenta) The shell is rimate perforate, elongate ovate, finely striated, polished, translucent, dark olive brown. The apex is round and obtuse. The shell contains four whorls, convex, tumid, wider at the base. The aperture is large, subcircular, with four obtuse teeth, one on the parietal margin, one on the columellar margin, and two on the outer lip. The peristome is slightly thickened and reflected. ^[2]

Distribution

This species is known to occur in a number of countries and islands including:

Distribution

• Texas,^[3] USA.
• Utah, USA^[4]
• Great Britain
• and other areas

References

• Gould, A. A. (1847). [Description] of a new species of Physa, together with two other new species of North American shells. Proceedings of the Boston Society of Natural History. 2: 262-263.
• Ancey, C. F. (1887). Description of North American shells. The Conchologists' Exchange. 2(6): 79-80.
• Bank, R. A.; Neubert, E. (2017). Checklist of the land and freshwater Gastropoda of Europe. Last update: July 16th, 2017.
• Sysoev, A. V. & Schileyko, A. A. (2009). Land snails and slugs of Russia and adjacent countries. Sofia/Moskva (Pensoft). 312 pp., 142 plates.