''Clappia umbilicata'', the umbilicate pebblesnail, was a

species In biology, a species is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of ...

of small

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 ...

that had an operculum, an aquatic gastropod

mollusk 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 es ...

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 ...

.Thompson F. G. (1984). "North American freshwater snail genera of the hydrobiid subfamily Lithoglyphinae". ''

Malacologia ''Malacologia'' is a peer-reviewed scientific journal in the field of malacology, the study of mollusks. The journal publishes articles in the fields of molluscan systematics, ecology, population ecology, genetics, molecular genetics, evolution, a ...

'' 25(1)
109
141. This species is now extinct.

Distribution

This species was

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found els ...

to the State of

Alabama (We dare defend our rights) , anthem = " Alabama" , image_map = Alabama in United States.svg , seat = Montgomery , LargestCity = Huntsville , LargestCounty = Baldwin County , LargestMetro = Greater Birmingham , area_total_km2 = 135,7 ...

in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...

. The

type locality Type locality may refer to: * Type locality (biology) * Type locality (geology) See also * Local (disambiguation) * Locality (disambiguation) {{disambiguation ...

is the

Coosa River The Coosa River is a tributary of the Alabama River in the U.S. states of Alabama and Georgia. The river is about long.U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map, accessed April 27, 2011 ...

Wetumpka, Alabama Wetumpka () is a city in and the county seat of Elmore County, Alabama, United States. At the 2020 census, the population was 7,220. In the early 21st century Elmore County became one of the fastest-growing counties in the state. The city is ...

. The distribution of this species used to include: Coosa River at Duncan's Ripple, The Bar and Higgin's Ferry in

Chilton County Chilton County is a county located in the central portion of the U.S. state of Alabama. As of the 2020 census, the population was 45,014. The county seat is Clanton. Its name is in honor of William Parish Chilton, Sr. (1810–1871), a law ...

; and Butting Ram Shoals in

Coosa County, Alabama Coosa County is located in the east central portion of the U.S. state of Alabama. As of the 2020 census the population was 10,387. Its county seat is Rockford. Its name derives from a town of the Creek tribe and the Coosa River, which forms o ...

.Clench W. J. (1965). "A new species of ''Clappia'' from Alabama". '' The Nautilus'' 79(1)
33
34
Figure 2
File:Map of Alabama highlighting Chilton County.svg,

Chilton County, Alabama Chilton County is a county located in the central portion of the U.S. state of Alabama. As of the 2020 census, the population was 45,014. The county seat is Clanton. Its name is in honor of William Parish Chilton, Sr. (1810–1871), a lawyer ...

(marked red) where the species was found File:Map of Alabama highlighting Coosa County.svg,

(marked red) where the species was also found

Description

This species was discovered and described under the name ''Somatogyrus umbilicatus'' by the American

malacologist Malacology is the branch of invertebrate zoology that deals with the study of the Mollusca (mollusks or molluscs), the second-largest phylum of animals in terms of described species after the arthropods. Mollusks include snails and slugs, clams, ...

Bryant Walker Bryant Walker (1856–1936) was an American malacologist who specialized in the non-marine Mollusca. He mainly studied the freshwater mollusks of the USA, in particular those of Michigan. He published many papers on the Unionida, an order of fr ...

in 1904. Walker's type description reads as follows: Clappia umbilicata radula

The color of ''Clappia umbilicata'' was black. This presumably means that the whole animal including

snout A snout is the protruding portion of an animal's face, consisting of its nose, mouth, and jaw. In many animals, the structure is called a muzzle, rostrum, or proboscis. The wet furless surface around the nostrils of the nose of many mammals is ...

, nape,

mantle A mantle is a piece of clothing, a type of cloak. Several other meanings are derived from that. Mantle may refer to: *Mantle (clothing), a cloak-like garment worn mainly by women as fashionable outerwear **Mantle (vesture), an Eastern Orthodox ve ...

and foot were black. The black color of the mantle was verified by Thompson (1984). ''Clappia umbilicata'' has 56-59 rows of teeth on its

radula The radula (, ; plural radulae or radulas) is an anatomical structure used by molluscs for feeding, sometimes compared to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food ...

. Each row has 6-7 central basocones, 6-7 central ectocones, 18-21 lateral teeth, ca. 50 inner marginal teeth and ca. 35 outer marginal teeth.

Ecology

The natural

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

of this species was

river A river is a natural flowing watercourse, usually freshwater Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. Although the ...

s. ''Clappia umbilicata'' inhabited only the rapidly flowing sections of river

shoals In oceanography, geomorphology, and geoscience, a shoal is a natural submerged ridge, bank, or bar that consists of, or is covered by, sand or other unconsolidated material and rises from the bed of a body of water to near the surface. It ...

. The snail died out because of

silting Siltation, is water pollution caused by particulate terrestrial clastic material, with a particle size dominated by silt or clay. It refers both to the increased concentration of suspended sediments and to the increased accumulation (temporary or ...

of its habitat after the

dam A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use, a ...

was constructed in 1928. (Also see Jordan Dam and

Jordan Lake B. Everett Jordan Lake is a reservoir in New Hope Valley, west of Cary and south of Durham in Chatham County, North Carolina, in the United States; the northernmost end of the lake extends into southwestern Durham County. Part of the J ...

). Based on examination of the radula, Thompson (1984) hypothesized that ''Clappia umbilicata'' grazed on fine particles of plants, specializing on finer-sized particles than those consumed by snails in the genus ''

Somatogyrus ''Somatogyrus'' is a genus of very small freshwater and brackish water snails that have an operculum, aquatic gastropod micromolluscs in the family Lithoglyphidae. Species Species within the genus ''Somatogyrus'' include: * Reverse pebblesna ...

''.

References

This article incorporates public domain text from reference {{Taxonbar, from=Q3138925 Lithoglyphidae Extinct gastropods Taxonomy articles created by Polbot Endemic molluscs of the United States Endemic fauna of Alabama