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definition - Freshwater_pearl_mussel

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Freshwater pearl mussel

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Freshwater pearl mussel
The exterior of the shell of Margaritifera margaritifera
Conservation status
Scientific classification
Species:M. margaritifera
Binomial name
Margaritifera margaritifera
Linneaus, 1758

The freshwater pearl mussel, scientific name Margaritifera margaritifera, is an endangered species of freshwater mussel, an aquatic bivalve mollusk in the family Margaritiferidae, the freshwater pearl mussels. The name "freshwater pearl mussel" should not be construed to mean that other freshwater mussels do not harbor pearls or cannot be used as mother of pearl. In fact most cultured pearls today come from Hyriopsis species in Asia, or Amblema species in North America, both members of the related family Unionidae.

The interior of the shell of this species has thick nacre. The species is capable of making fine quality pearls, therefore it was historically exploited in the search for pearls from wild sources.

Deutsche Post featured Margaritifera margaritifera on a 2002 German 0.56 postage stamp as part of a series on endangered species of animals [2].

Group of live Margaritifera margaritifera in a river bed in Sweden



Subspecies within the species Margaritifera magaritifera include:

  • Margaritifera margaritifera margaritifera (Linnaeus, 1758)
  • Margaritifera margaritifera parvula (Haas, 1908)
  • Margaritifera margaritifera durrovensis Phillips, 1928 - critically endangered subspecies in Ireland[3]. Synonym: Margaritifera durrovensis. This subspecies is mentioned in annexes II and V of Habitats Directive as Margaritifera durrovensis.
The interior of the shell of Margaritifera margaritifera, showing the nacre
The anatomy of Margaritifera margaritifera
1. Posterior adductor muscle
Anterior adductor muscle
3. Frontal gill
4. Back gill
5. Exhalant aperture
6. Inhalant aperture
7. Foot
8. Pseudotooth
9. The hingeline and ligament
10. Mantle
11. The shell's thickest part, the umbo


The native distribution of this species is Holarctic.

  • More than half the world's population exist in Scotland
  • North America: eastern Canada and New England at northwestern of the United States
  • Asia: Russian Federation
  • Continental Europe, including:


  1. ^ Mollusc Specialist Group (1996). Margaritifera margaritifera. 2006. IUCN Red List of Threatened Species. IUCN 2006. www.iucnredlist.org. Retrieved on 13 Jan 2007.
  2. ^ Andreas Bartl. [http://www.briefmarken-archiv.de/brd/01/2002/a020602.htm "Bauchige Windelschneckeund Flussperlmuschel"]. http://www.briefmarken-archiv.de/brd/01/2002/a020602.htm. Retrieved 2007-05-14.  (German)
  3. ^ 2007 IUCN Red List – Search
  4. ^ Juřičková L., Horsák M. & Beran L., 2001: Check-list of the molluscs (Mollusca) of the Czech Republic. Acta Soc. Zool. Bohem., 65: 25-40.
  5. ^ Red List of the molluscs (Mollusca) of the Czech Republic http://mollusca.sav.sk/malacology/redlist.htm
  6. ^ Dušek J., Hošek M. & Kolářová J. (2007) Hodnotící zpráva o stavu z hlediska ochrany evropsky významných druhů a typů přírodních stanovišť v České republice za rok 2004-2006. - Ochrana přírody, 62(5): appendix 5:I-IV. (in Czech language)
  7. ^ "Recherche de sites par espèce: Invertébrés: Moule perlière (Margaritifera margaritifera)". 2007. http://natura2000.environnement.gouv.fr/especes/1029.html. 
  8. ^ Glöer P. & Meier-Brook C. (2003) Süsswassermollusken. DJN, pp. 134, page 109, ISBN 3-923376-02-2
  9. ^ Protection for wild animals on Schedule 5 of the Wildlife and Countryside Act, 1981. website accessed 7 August 2009.
  10. ^ Joint Nature Conservation Committeewebsite]
  11. ^ Margaritifera margaritifera - Polska Czerwona Księga Zwierząt - Bezkręgowce
  12. ^ pl:Polska Czerwona Księga Zwierząt - Bezkręgowce
  13. ^ [1] cited 16 February 2007

Further reading

External links


All translations of Freshwater_pearl_mussel

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