The swan mussel, Anodonta cygnea, is a large species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of freshwater mussel, an aquatic

Aquatic animal

An aquatic animal is an animal, either vertebrate or invertebrate, which lives in water for most or all of its life. It may breathe air or extract its oxygen from that dissolved in water through specialised organs called gills, or directly through its skin. Natural environments and the animals that...

 bivalve mollusc in the family

Family (biology)

In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Unionidae

Unionidae

Unionidae is a family of freshwater mussels, the largest in the order Unionoida, the bivalve mollusks sometimes known as river mussels, naiads, or simply as unionids.The range of distribution for this family is world-wide...

, the river mussels.

Because of its morphological variability, and its wide range of distribution, there are over 500 synonyms

Synonym (taxonomy)

In scientific nomenclature, a synonym is a scientific name that is or was used for a taxon of organisms that also goes by a different scientific name. For example, Linnaeus was the first to give a scientific name to the Norway spruce, which he called Pinus abies...

 for this species.

Shell description

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.

Distribution

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.

• Croatia
• 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.
• Germany
  Germany
  Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
  
  
  • Germany - highly endangered (Stark gefährdet)
  • Listed as specially protected species in annex 1 in Bundesartenschutzverordnung.
• The Netherlands - yes
• Poland - endangered
• Slovakia
• Sweden - quite rare
• British Isles
• Italy
• Portugal

Life habits

External links

• PAN Pesticides Database - Chemical Toxicity Studies