Viviparidae, commonly called river snails or mystery snails, are a family of with gills and a protective lid (operculum). Recent studies show that their family tree is more complex than expected, with genetic evidence suggesting some species don't fit neatly into traditional groups.
Distribution
This family occurs nearly worldwide in temperate and tropical regions, with the exception that they are absent from
South America.
There are two genera of Viviparidae in Africa: Bellamya and Neothauma.
The oldest known vivparid is Viviparus langtonensis from the Middle Jurassic of England.
Viviparidae snails live in freshwater spots like rivers and lakes across Europe, Asia, and parts of North America. Recent surveys show they're spread out widely in places like Russia and China, adapting well to different environments
Taxonomy and phylogeny
The family Viviparidae contains 3 subfamilies (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005):
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Viviparinae Gray, 1847 (1833) - synonyms: Paludinidae Fitzinger, 1833 (inv.); Kosoviinae Atanackovic, 1859 (n.a.)
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Bellamyinae Rohrbach, 1937 - synonym: Amuropaludinidae Starobogatov, Prozorova, Bogatov & Sayenko, 2004 (n.a.)
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Lioplacinae Gill, 1863 - synonym: Campelomatinae Thiele, 1929
Scientists used to group Viviparidae snails based on how they look, but new research using DNA has shaken things up. Studies of snail genes, like those from species such as
Viviparus chui and
Cipangopaludina chinensis, show that some don't belong where we thought they did, making the family tree more complicated than expected
.In Japan, DNA tests on snails like
Sinotaia quadrata histrica also found differences between what their genes say and how they've been classified before.
This means figuring out how these snails are related is still a work in progress.
Morphology and evolution
Viviparidae snails have shells that can look different depending on where they live, and early studies suggest their surroundings help shape them over time. A scientist named Annandale found that things like water conditions might change how their shells grow, making them better suited to freshwater life
.Today, research on snails like
Cipangopaludina japonicashows their shells and bodies are built in ways that help them thrive, even in new places where they've spread.
These snails can live anywhere from 3 to 11 years, depending on their environment.
Genera
Genera within the family Viviparidae include:
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subfamily Viviparinae Gray, 1847
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subfamily Bellamyinae Rohrbach, 1937
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Amuropaludina Moskvicheva, 1979
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Angulyagra Rao, 1931
[(file created 29 July 2010) FRESH WATER MOLLUSCAN SPECIES IN INDIA. 11 pp. accessed 31 July 2010.]
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Anulotaia Brandt, 1968
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Anularya Zhang & Chen, 2015
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† Apameaus Sivan, Heller & van Damme, 2006
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Bellamya Jousseame, 1886 - type genus of the subfamily
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Boganmargarya Thach, 2018
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Cipangopaludina Hannibal, 1912
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Eyriesia P. Fischer, 1885
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Filopaludina Habe, 1964
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Heterogen Annandale, 1921 - with the only species Heterogen longispira (E. A. Smith, 1886)
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Idiopoma Pilsbry, 1901
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Larina Adams, 1851
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Margarya Nevill, 1877
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Mekongia Crosse & Fischer, 1876
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Neclarina Iredale, 1943
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Notopala Cotton, 1935
[ River Snail ( Notopala sublineata). accessed 26 September 2010]
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Sinotaia Haas, 1939
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Taia Annandale, 1918
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† Temnotaia Annandale, 1919
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Tchangmargarya He, 2013
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Torotaia Haas, 1939
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Trochotaia Brandt, 1974
[Du L.-N., Yang J.-X. & Chen X.-Y. (2011). "A new species of Trochotaia (Caenogastropoda: Viviparidae) from Yunnan, China". Molluscan Research 31(2): 85-89. abstract]
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subfamily?
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† Albianopalin Hamilton-Bruce, Smith & Gowlett-Holmes, 2002
[Hamilton-Bruce R. J., Smith B. J. & Gowlett-Holmes K. L. (2002). "Descriptions of a new genus and two new species of viviparid snails (Mollusca: Gastropoda: Viviparidae) from the Early Cretaceous (middle-late Albian) Griman Creek Formation of Lightning Ridge, northern New South Wales". Records of the South Australian Museum 35': 193–203. PDF] - from Albian, New South Wales
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Neothauma E. A. Smith, 1880
[Brown D. S. (1994). Freshwater Snails of Africa and their Medical Importance. Taylor & Francis. .]
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Siamopaludina Brandt, 1968
- Genera brought into synonymy
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Centrapala Cotton, 1935:
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Contectiana Bourguignat, 1880: synonym of Viviparus Montfort, 1810
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Eularina Iredale, 1943: synonym of Larina A. Adams, 1855
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subfamily † Kosoviinae Atanacković, 1959: synonym of Viviparidae Gray, 1847
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Lecythoconcha Annandale, 1920: synonym of Cipangopaludina Hannibal, 1912
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Metohia Popović, 1964 : (junior homonym, no replacement name available in 2014)
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Notopalena Iredale, 1943: synonym of Notopala Cotton, 1935
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Paludina Férussac, 1812: synonym of Viviparus Montfort, 1810
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Siamopaludina Brandt, 1968 : synonym of Filopaludina (Siamopaludina) Brandt, 1968 represented as Filopaludina Habe, 1964
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Vivipara : synonym of Viviparus Montfort, 1810
Lifecycle
Viviparidare are viviparous: they give birth to live offspring instead of laying eggs.
First, internal fertilization occurs, and from the on embryos continue to develop within the female's brood pouch. Here, they are nourished until they are matured. Once matured, the offsprings are released into the water as miniature versions of the adults. This method has shown to increase their chances of survival in freshwater environments.
Life spans have been reported from 3 to 11 years in various species of Viviparidae, depending on environmental conditions and species type.
Fossil record
Viviparidae snails have been around for a long time, and their fossils, like
Viviparus langtonensis, show they've lived in freshwater for millions of years. Recent DNA studies back this up, hinting at how these snails split into different types way back in history.
These old clues help us understand where they came from and how they've changed. They are snails.
Further reading
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Hirano T., Saito T. & Chiba S. (2015). "Phylogeny of freshwater viviparid snails in Japan". Journal of Molluscan Studies 81(4): 435–441. .
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Qian Z.-X., Fang Y.-F. & He J. (2014). "A conchological review of Bellamyinae (Gastropoda: Viviparidae) of China". Shell Discoveries 1(3): 3-12.
External links
