Patera clarki nantahala

Patera clarki nantahala, common names the noonday globe, noonday snail or noonday helix, is a subspecies of the species Patera clarki, a medium-sized, air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Polygyridae.

The name "nantahala" is a Cherokee word which means noonday. This subspecies was given this name because the snail lives in a deep gorge where the sunshine does not reach the ground until the middle of the day.^[3]

Contents 1 Shell description 2 Anatomy 3 Distribution 4 Ecology 4.1 Habitat 4.2 Feeding habits 4.3 Life cycle 4.4 Interspecific relationships 5 References 6 Further reading

Shell description

The shell of the noonday globe snail is moderately sized (3/4 inch wide and 1/2 inch high) and globose in shape. The outer shell surface is shiny and reddish in color.

Shells of this subspecies often exhibit 5 and half whorls.^[4] The shell surface is sculptured with rather coarse lines. The area around the shell opening (aperture) is white, and a long curved "tooth" is located on the inside portion of the aperture.

The width of the shell is 18 mm. The height of the shell is 11 mm.^[4]

Anatomy

The animal's body is black in color.

Distribution

Patera clarki nantahala is an endemic subspecies, part of the wildlife of North Carolina.^[5]

Its distribution is restricted to part of the Nantahala Gorge, in the Appalachian Mountains, in Swain County, North Carolina.

The noonday globe snail is known from a small area: approximately 2 miles of high cliffs within the Nantahala Gorge, on the east side of the gorge.^[4]

The noonday globe snail was probably never widely distributed. Its preferred habitat of steep wet slopes with calcareous rocks is rare in western North Carolina. However, the subspecies was probably more widely distributed within the gorge before the gorge itself was altered for a railroad and a highway U.S. Route 19. Both of these projects altered the forest community along the river. The associated loss of the forest canopy allowed more sunlight to penetrate the gorge, and dried out the lower slope. This habitat alteration allowed such non-native plants as Kudzu and Japanese honeysuckle to invade some roadside areas, and changed the area's natural plant and animal community.

In an attempt to secure the snail's continued existence, the United States Fish and Wildlife Service added it as a threatened subspecies, to the Federal Endangered and Threatened Species List on July 3, 1978.^[6] It is a Federal offense punishable by as much as a $50,000 fine and one year in jail for taking a noonday snail.

Ecology

Because this snail is so rare and restricted in distribution, very little is known of its biology.

Habitat

This land snail is found in damp oak-hickory forest.^[4]

The cliffs in the Nantahala Gorge region are very wet, intersected by many small streams and waterfalls. The forest is mature, with many large trees and a diverse plant community. The forest floor has a thick, rich humus layer, and the area has many exposed limestone rocks. Calcium carbonate, which is generally scarce in other cliffs in the area, is vital to most snails, because it is a major component of their shells. The rich, moist calcareous soils, and the mature forest community are likely to account for the unusually wide variety of snails which inhabit the area; Patera clarki nantahala being found in association with 29 other snail species.

This subspecies appears to be most active during wet weather, when it is frequently found out on the surface of vegetation, rather than under the leaf litter on the forest floor.

Feeding habits

The feeding habits of Patera clarki are unknown, but other related species in the genus Patera feed on fungus, in particular the subsurface, hair-like structures called (mycelia).

Life cycle

This subspecies' reproductive behavior is currently unknown.

Interspecific relationships

Snails are usually exploited as a food source by other animals. A common carnivorous land snail, Haplotrema concavum, was observed eating a noonday globe snail, and gnawed shells of the other subspecies of this snail, Patera clarki clarki, have been found in the dens of small rodents.

References

This article incorporates public domain text (a public domain work of the United States Government) from:

• U.S. Fish and Wildlife Service. 2008. Noonday Globe in North Carolina. <http://www.fws.gov/nc-es/snail/noonglobe.html>, accessed 1 November 2008. (nearly the same text is also at http://www.fws.gov/asheville/htmls/recoveryandlistedspecies/species_sites/Noonday_globe.html)

Further reading

• Author unknown, March 13 1996. (DRAFT) SNAIL, NOONDAY. available at http://fwie.fw.vt.edu/WWW/esis/lists/e354003.htm
• U.S. Fish and Wildlife Service. 1984. Recovery Plan for the Noonday Snail. U.S. Fish and Wildlife Service. Atlanta, GA. 30 pp.