Valvata cristata

Valvata cristata is a species of minute freshwater snail with an operculum, an aquatic gastropod mollusk or micromollusk in the family Valvatidae, the valve snails.

Valvata cristata
Five views of a shell of Valvata cristata
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
Family:	Valvatidae
Genus:	Valvata
Species:	V. cristata
Binomial name
Valvata cristata O. F. Müller, 1774[1]

Distribution

• Czech Republic - Bohemia and Moravia^[2]
• Slovakia^[2]
• Poland
• Germany - (Arten der Vorwarnliste)^[3]
• Netherlands
• the British Isles: Great Britain and Ireland
• Hungary
• Kaliningrad Oblast, Russia^[4]
• and other areas

Specimens of V.cristata in Naturalis Biodiversity Center. Note the tiny size

Shell description

The shell of this exceeding small (2–4 mm) Valvata species is very flat in its coiling, and therefore it somewhat resembles a Planorbis shell. However, the shell is dextral in coiling and has an operculum.^[5] The shell is transparent, has 3-3.5 whorls in a circular aperture. The umbilicus is wide and open, more than 1/3 of shell diameter.

Ecology

This species lives in stagnant and slow-moving water.

Myzyk (2002)^[6] described life cycle of Valvata cristata.

References

1. Müller O. F. (1774). Vermivm terrestrium et fluviatilium, seu animalium infusoriorum, helminthicorum, et testaceorum, non marinorum, succincta historia. Volumen alterum. pp. I-XXVI [= 1-36], 1-214, [1-10]. Havniae & Lipsiae. (Heineck & Faber).
2. (in Czech) Horsák M., Juřičková L., Beran L., Čejka T. & Dvořák L. (2010). "Komentovaný seznam měkkýšů zjištěných ve volné přírodě České a Slovenské republiky. [Annotated list of mollusc species recorded outdoors in the Czech and Slovak Republics]". Malacologica Bohemoslovaca, Suppl. 1: 1-37. PDF.
3. (in German) Glöer P. & Meier-Brook C. (2003) Süsswassermollusken. DJN, pp. 134, page 106, ISBN 3-923376-02-2
4. Filippenko D. (2011). "Fauna of gastropod molluscs in the Curonian Lagoon littoral biotopes (Baltic Sea, Kaliningrad region, Russia)". Malacologica Bohemoslovaca 10: 79–83. PDF.
5. Janus, Horst (1965). ‘’The young specialist looks at land and freshwater molluscs’’, Burke, London
6. Myzyk S. (2002). "Life cycle of Valvata cristata O. F. Müller, 1774 (Gastropoda: Heterobranchia) in the laboratory". Folia Malacologica 10(2): 47-75. PDF.

External links

• Valvata cristata at Animalbase taxonomy,short description, distribution, biology,status (threats), images
• Ulster Museum Image