The golden pebblesnail,

scientific name In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

''Somatogyrus aureus'', is a species of minute

freshwater snail Freshwater snails are gastropod mollusks which live in fresh water. There are many different families. They are found throughout the world in various habitats, ranging from ephemeral pools to the largest lakes, and from small seeps and springs ...

s with an operculum, aquatic

gastropod The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...

mollusc Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is esti ...

s or

micromollusc A micromollusk is a shelled mollusk which is extremely small, even at full adult size. The word is usually, but not exclusively, applied to marine mollusks, although in addition, numerous species of land snails and freshwater mollusks also r ...

s in the family

Lithoglyphidae Lithoglyphidae is a family of small freshwater snails with gills and an operculum, aquatic gastropod mollusks. This family is in the superfamily Truncatelloidea and in the clade Littorinimorpha (according to the taxonomy of the Gastropoda by ...

. This species is endemic to Alabama and Tennessee in the United States. Its natural habitat is the Tennessee River system, with the type locality being given as the Holston River. The taxonomic status of ''S. aureus'' is unclear, as it is morphologically similar to other species. However, if it is a valid species, it would be assessed as '' Critically Endangered (possibly extinct)''. Although the

IUCN The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...

officially categorises the species as

Data Deficient A data deficient (DD) species is one which has been categorized by the International Union for Conservation of Nature (IUCN) as offering insufficient information for a proper assessment of conservation status to be made. This does not necessaril ...

, it also considers it as ''

Possibly extinct The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biologi ...

'', as it has not been definitively recorded alive since the river was impounded in 1936. A purported finding from

Marion County, Tennessee Marion County is a county located in the U.S. state of Tennessee. It is located in East Tennessee. As of the 2020 census, the population was 28,837. Its county seat is Jasper. Marion County is part of the Chattanooga, AL– TN– GA Metropol ...

in 1997Shelton, D.N. 1997. Observations on the life history of the Alabama pearl shell, ''Margaritifera marrianae'' R. I. Johnson, 1983. Conservation and Management of Freshwater Mussels II: initiatives for the future. In: Cummings, K.S, Buchanan, A.C., Mayer, C.A. and Naimo, T.J. (eds), Proceedings of a UMRCC Symposium, pp. 26-29. Upper Mississippi River Conservation Committee, Rock Island, Illinois. St. Louis, Missouri has yet to be confirmed.

References

Endemic molluscs of the United States Somatogyrus Gastropods described in 1865 Taxa named by George Washington Tryon Taxonomy articles created by Polbot {{Lithoglyphidae-stub