Clappia umbilicata


The umbilicate pebblesnail, scientific name Clappia umbilicata, was a species of small freshwater snail that had an operculum, an aquatic gastropod mollusk in the family Lithoglyphidae. This species is now extinct.

Distribution

This species was endemic to the State of Alabama in the United States. The type locality is the Coosa River at Wetumpka, Alabama.
The distribution of this species used to include: Coosa River at Duncan's Ripple, The Bar and Higgin's Ferry in Chilton County; and Butting Ram Shoals in Coosa County, Alabama.

Description

This species was discovered and described under the name Somatogyrus umbilicatus by the American malacologist Bryant Walker in 1904. Walker's type description reads as follows:
r teeth of Clappia umbilicata: central tooth, lateral tooth, inner marginal tooth and outer marginal tooth.
The color of Clappia umbilicata was black. This presumably means that the whole animal including snout, nape, mantle and foot were black. The black color of the mantle was verified by Thompson.
Clappia umbilicata has 56-59 rows of teeth on its radula. Each row has 6-7 central basocones, 6-7 central octocones, 18-21 lateral teeth, ca. 50 inner marginal teeth and ca. 35 outer marginal teeth.

Ecology

The natural habitat of this species was rivers. Clappia umbilicata inhabited only the rapidly flowing sections of river shoals. The snail died out because of silting of its habitat after the dam was constructed in 1928..
Based on examination of the radula, Thompson hypothesized that Clappia umbilicata grazed on fine particles of plants, specializing on finer-sized particles than those consumed by snails in the genus Somatogyrus.