Athearnia
Encyclopedia
Athearnia is a genus
of freshwater
snail
s with a gill
and an operculum
, aquatic gastropod mollusks in the family Pleuroceridae
.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of freshwater
Freshwater
Fresh water is naturally occurring water on the Earth's surface in ice sheets, ice caps, glaciers, bogs, ponds, lakes, rivers and streams, and underground as groundwater in aquifers and underground streams. Fresh water is generally characterized by having low concentrations of dissolved salts and...
snail
Snail
Snail is a common name applied to most of the members of the molluscan class Gastropoda that have coiled shells in the adult stage. When the word is used in its most general sense, it includes sea snails, land snails and freshwater snails. The word snail without any qualifier is however more often...
s with a gill
Gill
A gill is a respiratory organ found in many aquatic organisms that extracts dissolved oxygen from water, afterward excreting carbon dioxide. The gills of some species such as hermit crabs have adapted to allow respiration on land provided they are kept moist...
and an operculum
Operculum (gastropod)
The operculum, meaning little lid, is a corneous or calcareous anatomical structure which exists in many groups of sea snails and freshwater snails, and also in a few groups of land snails...
, aquatic gastropod mollusks in the family Pleuroceridae
Pleuroceridae
Pleuroceridae, common name pleurocerids, is a family of small to medium-sized freshwater snails, aquatic gilled gastropod mollusks in the superfamily Cerithioidea.These snails have an operculum and typically a robust high-spired shell....
.
Species
Species within the genus Athearnia include:- Athearnia anthonyiAthearnia anthonyiAthearnia anthonyi is a rare species of freshwater snail in the family Pleuroceridae. Its common name is Anthony's riversnail. It is native to three rivers in the Tennessee River system in the United States: the main branch and the Sequatchie River and Limestone Creek....
- Athearnia crassa, the boulder snailBoulder snailThe boulder snail, scientific name †Athearnia crassa, was a species of freshwater snail, a gastropod in the family Pleuroceridae. This species was endemic to the United States, but it is now extinct.-References:...