Painted Rocksnail

Leptoxis taeniata

Description

The Leptoxis taeniata, (painted rocksnail) is a small to medium snail about 0.8 in (2 cm) in length, and subglobose to oval in shape. The aperture is broadly ovate, and rounded anteriorly. Coloration varies from yellowish to olive-brown, and usually with four dark bands. Some shells may not have bands and some have the bands broken into squares or oblongs. All of the rocksnails that historically inhabited the Mobil River Basin had broadly rounded apertures, oval shaped shells, and variable coloration. Although the various species were distinguished by relative sizes, coloration patterns, and ornamentation, identification could be confusing. However, the painted rocksnail is the only known survivor of the 15 rocksnail species that were historically known from the Coosa River drainage.

Behavior

The painted rocksnail is known to graze on algae found on rocks. In addition, the painted rocksnail lays its eggs on rocks in order to reproduce.

Habitat

Painted snails are found attached to cobble, gravel, or other hard substrates in the strong currents of riffles and shoals of rivers and streams. Adult rocksnails move very little, and females probably glue their eggs to stones in the same habitat.

Distribution

The painted rocksnail had the largest range of any rocksnail in the Mobile River Basin. It was historically known from the Coosa River and tributaries from the northeastern corner of St. Clair County, Alabama, downstream into the mainstem of the Alabama River to Claiborne, Monroe County, Alabama, and the Cahaba River below the Fall Line in Perry and Dallas Counties, Alabama. Surveys by Service biologists and others in the Cahaba River, unimpounded portions of the Alabama River, and a number of free-flowing Coosa River tributaries have located only three localized Coosa River drainage populations.

The painted rocksnail is currently known from the lower reaches of three Coosa River tributaries— Choccolocco Creek, Talladega County; Buxahatchee Creek, Shelby County; and Ohatchee Creek, Calhoun County, Alabama.

Threats

The painted rocksnail has lost more than 90% of its historical range because of habitat destruction caused by impoundment, and pollution by siltation and chemicals associated with coal mining and land-use practices. It is now known from only three distinct drainage localities. Extant populations and colonies of these three species are localized, isolated, and are vulnerable to water quality degradation, future human activities that would degrade their habitats, and random catastrophic events.

Conservation and Recovery

The painted rocksnail only survives in three small, isolated, critical habitats. These are tributaries of the Coosa River: Choccolocco Creek, Buxahatchee Creek, and Ohatchee Creek. It is crucial that its few critical habitats are protected from any proposed impoundment, and from pollution associated with coal mining, agricultural land-use, or other sources. The surviving populations of the painted rocksnail should be monitored, and research undertaken into its biology and ecological needs, including work on its propagation. If suitable habitat can be found, additional populations should be established.

Contacts

U. S. Fish and Wildlife Service
Jackson Ecological Services Field Office
6578 Dogwood View Parkway, Suite A
Jackson, Mississippi 39213-7856
Telephone: (601) 965-4900

U. S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
1875 Century Blvd., Suite 200
Atlanta, Georgia 30345
http://southeast.fws.gov/

Reference

U.S. Fish and Wildlife Service. 28 October 1998. "Endangered and Threatened Wildlife and Plants; Endangered Status for Three Aquatic Snails, and Threatened Status for Three Aquatic Snails in the Mobile River Basin of Alabama." Federal Register 63(208):57610-57620.