This species can be found throughout Europe from Portugal in the southwest as far east as Siberia (Zettler et al. 2006). However, there are no data to support species presence within Siberia (Vinarski et al. 2007). Mozley (1936) also described this species from northern Asia but molecular studies should confirm the validity of this claim. It has also been recorded in Northern Iran (Pourang et al. 2009). In Russia, it is found throughout the European part of the state (Kantor et al. 2009). The Iberian populations are restricted to three small lagoons in a 50 km radius in Portugal and it is possibly extinct from Spain after recent construction works in the Valencia albufera (lagoon) by the Mediterranean sea (Araujo pers comm.). A recent record of Anodonta cygnea has been published from Algeria (Khalloufi and Boumaiza 2005) but the validity of the species should also be confirmed with molecular characterization.
Habitat and Ecology
This species primarily inhabits closed off and small waters such as ponds and peatlands, but can also be found occupying lakes and slow-flowing lowland rivers (Zettler et al. 2006). It is also found in canals, drainage dykes and dam reservoirs (Killeen et al. 2004). The species appears to prefer waterbodies characterized by high concentrations of dissolved oxygen (a likely consequence of the species' fast growth and large size), free from floating vegetation and with fertile bottom sediments (Zając 2002, Rosińska et al. 2008). The species is intolerant of poor environmental conditions, and can be used as a bioindicator of clean water (Rosińska et al. 2008). When present, it is often the only mussel species inhabiting these areas (Zettler et al. 2006). The species is able to use a wide range of host fish (both invasive and native fish) for larvae dispersal and metamorphosis (Giusti et al. 1975, Lopes-Lima pers. comm.)
Molecular Biology and Genetics
Barcode data: Anodonta cygnea
Below is a sequence of the barcode region Cytochrome oxidase subunit 1 (COI or COX1) from a member of the species.
See the BOLD taxonomy browser for more complete information about this specimen and other sequences.
-- end --
Download FASTA File
Statistics of barcoding coverage: Anodonta cygnea
Public Records: 5
Specimens with Barcodes: 6
Species With Barcodes: 1
IUCN Red List Assessment
Red List Category
Red List Criteria
- 2011Least Concern
Although this species is widespread and considered fairly common (Zettler et al. 2006) not many studies have been carried to assess populations’ size and structure. In Poland this species has been declining since the 1950s due to habitat degradation and pollution (Zając 2005). In Britain, river management strategy includes the dredging of rivers which can remove 20% of British subpopulations (Aldridge 2001). At the southeastern edge of its range, the Iberian populations are only restricted to three small lagoons that have been recently invaded by water hyacinth (crassipes spp.) with very negative impacts (Lopes-Lima pers. com.) No detailed population trend data are known.
This species has been badly impacted by the zebra mussel Dreissena polymorpha and has suffered localised declines in areas where this species has invaded its habitats (Byrne et al. 2009). In the absence of suitable substrate, Anodonta species are known to be a preferred settlement site for zebra mussels. Heavy infestations can affect the feeding, respiration and reproduction of unionid bivalves, causing mortality and eliminating entire populations (Rosell et al. 1999). The continued range expansion of D. polymorpha into suitable habitat is likely to further impact this species' population numbers (Byrne et al. 2009).
Localized declines have been reported in Poland as a result of habitat degradation, water pollution and eutrophication (Dyduch-Falniowska 1992, cited in Mills and Reynolds 2004). The species is also threatened as a result of poaching for supply in artificial basins and garden ponds (Rosińska et al. 2008). In Britain, poor river management is a significant threat to the species: dredging occurs approximately every ten years and can remove 20% of unioid populations (Aldridge 2001).
The recent invasion of the water hyacinth in the few freshwater lagoons of Iberia is menacing the whole population in this fringe of the distribution (Lopes-Lima pers. com.)
Further research is currently needed into the species' global population to assess the impacts of the documented threat processes.
The shell is thin but large (approximately 10 to 20 cm) and rather flat, even at the umbo. The shell color is often pale greenish or brownish.For differences from Anodonta anatina see Animalbase below (external links).
Its native distribution is European-Siberian. The geographical distribution of this species is from the British Isles east to Siberia, and south into northern Africa.
- Czech Republic - in Bohemia, in Moravia, vulnerable (VU); Czech code, Decree for implementation, No. 395/1992 Sb. (and No. 175/2006 Sb.) - Highly threatened species.
- The Netherlands - yes 
- Poland - endangered
- Sweden - quite rare 
- British Isles including Ireland
This species is found in rivers and lakes.
- Lopes-Lima, M. (2014). "Anodonta cygnea". IUCN Red List of Threatened Species. Version 2014.1. International Union for Conservation of Nature. Retrieved 1 July 2014.
- http://mussel-project.ua.edu/tax/intro/overnamed.html Accessed 17 November 2010.
- (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.
- Red List of the molluscs (Mollusca) of the Czech Republic http://mollusca.sav.sk/malacology/redlist.htm
- Glöer P. & Meier-Brook C. (2003) Süsswassermollusken. DJN, pp. 134, page 109, ISBN 3-923376-02-2
- Anodonta cygnea - Polska Czerwona Księga Zwierząt - Bezkręgowce
- pl:Polska Czerwona Księga Zwierząt - Bezkręgowce
-  cited 16 February 2007
EOL content is automatically assembled from many different content providers. As a result, from time to time you may find pages on EOL that are confusing.
To request an improvement, please leave a comment on the page. Thank you!