Borysthenia
Encyclopedia
Borysthenia is a genus
of small freshwater snail
s with an operculum
, aquatic
gastropod mollusks in the family Valvatidae
, the valve snails.
The aperture
of Borysthenia is not circular. Animals are ovoviviparous.
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 small freshwater snail
Freshwater snail
A freshwater snail is one kind of freshwater mollusc, the other kind being freshwater clams and mussels, i.e. freshwater bivalves. Specifically a freshwater snail is a gastropod that lives in a watery non-marine habitat. The majority of freshwater gastropods have a shell, with very few exceptions....
s with 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
Aquatic animal
An aquatic animal is an animal, either vertebrate or invertebrate, which lives in water for most or all of its life. It may breathe air or extract its oxygen from that dissolved in water through specialised organs called gills, or directly through its skin. Natural environments and the animals that...
gastropod mollusks in the family Valvatidae
Valvatidae
Valvatidae, the valve snails, is a taxonomic family of very small freshwater snails with an operculum, aquatic gastropod mollusks.- Taxonomy :...
, the valve snails.
The aperture
Aperture (mollusc)
The aperture is an opening in certain kinds of mollusc shells: it is the main opening of the shell, where part of the body of the animal emerges for locomotion, feeding, etc....
of Borysthenia is not circular. Animals are ovoviviparous.
Species
The genus Borysthenia contains the following species:- † Borysthenia goldfussianaBorysthenia goldfussiana†Borysthenia goldfussiana is an extinct species of small freshwater snail with a gill and an operculum, an aquatic gastropod mollusk in the family Valvatidae, the valve snails....
(Wüst, 1901) - † Borysthenia intermedia Kondrashov, 2007 - from the Middle Pleistocene of OkaOka RiverOka is a river in central Russia, the largest right tributary of the Volga. It flows through the regions of Oryol, Tula, Kaluga, Moscow, Ryazan, Vladimir, and Nizhny Novgorod and is navigable over a large part of its total length, as far upstream as to the town of Kaluga. Its length exceeds...
-DonDon River (Russia)The Don River is one of the major rivers of Russia. It rises in the town of Novomoskovsk 60 kilometres southeast from Tula, southeast of Moscow, and flows for a distance of about 1,950 kilometres to the Sea of Azov....
Plain - Borysthenia menkeana (Jelski, 1863)
- Borysthenia naticinaBorysthenia naticinaBorysthenia naticina is a species of small freshwater snail with a gill and an operculum, an aquatic gastropod mollusk in the family Valvatidae, the valve snails.-Distribution:This species occurs in the Pontic and Baltic regions as follows:...
(Menke, 1845) - type species as Valvata jelskii Crosse, 1863