Borysthenia

Borysthenia is a genus of small freshwater snails with an operculum, aquatic gastropod mollusks in the family Valvatidae, the valve snails.

Borysthenia Temporal range: at least from Middle Pleistocene[1]-Recent PreꞒ Ꞓ O S D C P T J K Pg N ↓
Subfossil shells of Borysthenia naticina
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
(unranked):	clade Heterobranchia informal group Lower Heterobranchia
Superfamily:	Valvatoidea
Family:	Valvatidae
Genus:	Borysthenia Lindholm, 1913[2]

The aperture of Borysthenia is not circular.[3] Animals are ovoviviparous.[3]

Species

The genus Borysthenia contains the following species:

• † Borysthenia goldfussiana (Wüst, 1901)
• † Borysthenia intermedia Kondrashov, 2007 - from the Middle Pleistocene of Oka-Don Plain[1]
• Borysthenia menkeana (Jelski, 1863)
• Borysthenia naticina (Menke, 1845) - type species as Valvata jelskii Crosse, 1863[3]

References

1. Kondrashov P. E. (2007). "New gastropod species from the Pleistocene of the Upper Don basin". Paleontological Journal 41(5): 513-519. doi:10.1134/S0031030107050061.
2. Lindholm W. A. (1913). "Miszellen zur Malakozoologie des Russischen Reiches. I-XIII." Ezhegodnik Zoologicheskago Muzeya Imperatorskoj Akademii Nauk - Annuaire due Musée Zoologique de l'Académie Impériale des Sciences de St.-Pétersbourg 18(1): 151-167. page 167.
3. "Genus summary for Borysthenia". AnimalBase, last modified 28 February 2009, accessed 22 May 2011.