Sphaerium

Sphaerium is a genus of very small freshwater clams, aquatic bivalve molluscs in the family Sphaeriidae, known as the fingernail clams. The small clams in this genus are unusual in that many of them, such as Sphaerium corneum, can climb around underwater on aquatic plants, using their long and strong foot.

Sphaerium
Sphaerium corneum
Live Sphaerium sp. moving around with its foot. Collected from a pond in Portland, Oregon
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Bivalvia
Order:	Sphaeriida
Superfamily:	Sphaerioidea
Family:	Sphaeriidae
Genus:	Sphaerium Scopoli, 1777
Species
See text.
Synonyms
List Amesoda Rafinesque, 1820 Amesoda (Asiocyclas) Starobogatov & Korniushin, 1986 Amesoda (Clessinicyclas) Alimov & Starobogatov, 1968 Amesoda (Cyrenastrum) Bourguignat, 1854 Amesodon Agassiz, 1846 Calyculina Clessin, 1872 Clessinicyclas Alimov & Starobogatov, 1968 Cornea Megerle von Mühlfeld, 1811 Corneocyclas J. B. Férussac, 1818 Corneola Westerlund, 1873 Cycladea Rafinesque, 1815 Cycladites Krüger, 1823 Cyclas Lamarck, 1798 Cyclas (Amesoda) Rafinesque, 1820 Cyclas (Cyclas) Lamarck, 1798 Cyclas (Phymesoda) Rafinesque, 1820 Cyclas (Securilla) Drouët, 1855 Cyclas (Sphaerium) Scopoli, 1777 Cyclocalyx (Sphaerinova) Iredale, 1943 Cyclus Jurine, 1817 Cyrena (Corneocyclas) Blainville, 1818 Cyrena (Cyclas) Lamarck, 1798 Cyrena (Sphaerium) Scopoli, 1777 Musculium Link, 1807 Musculium (Morimusculium) Starobogatov, 1986 Musculium (Musculium) Link, 1807 Musculium (Paramusculium) Alimov & Starobogatov, 1968 Musculium (Parvimusculium) Starobogatov & Kornjushin, 1986 Musculium (Patagomusculium) Starobogatov, 1986 Musculium (Sphaerinova) Iredale, 1943 Nucleocyclas Alimov & Starobogatov, 1968 Nux Humphrey, 1797 Paramusculium Alimov & Starobogatov, 1968 Phymesoda Rafinesque, 1820 Primella Cooper, 1892 · unaccepted Pseudocorbicula Dautzenberg, 1908 Rivicoliana Servain, 1888 Shadinicyclas Starobogatov & Korniushin, 1986 Sphaeriastrum Bourguignat, 1854 Sphaerinova Iredale, 1943 Sphaerinova (Asiomusculium) Starobogatov & Korniushin, 1986 Sphaerium (Amesoda) Rafinesque, 1820 Sphaerium (Baicaliana) Korniushin, 1996 Sphaerium (Corneana) Servain, 1888 Sphaerium (Corneola) Westerlund, 1873 Sphaerium (Cyclas) Lamarck, 1798 Sphaerium (Cyrenastrum) Bourguignat, 1854 Sphaerium (Herringtonium) A. H. Clarke, 1973 Sphaerium (Lacustriana) Servain, 1888 Sphaerium (Musculium) Link, 1807 Sphaerium (Nucleocyclas) Alimov & Starobogatov, 1968 Sphaerium (Pseudocorbicula) Dautzenberg, 1908 Sphaerium (Rivicoliana) Servain, 1888 Sphaerium (Serratisphaerium) Germain, 1909 Sphaerium (Sibirisphaerium) Slugina & Starobogatov, 1994 Sphaerium (Solidiana) Servain, 1888 Sphaerium (Sphaeriastrum) Bourguignat, 1854 Sphaerium (Sphaerinova) Iredale, 1943 Sphaerium (Sphaerium) Scopoli, 1777 Zecyclas Starobogatov, 1968

Selected species

Main article: List of Sphaerium species

The following species are included in the genus Sphaerium:^[1]

• Sphaerium asiaticum (E. von Martens, 1864)
• †Sphaerium beckmani L. S. Russell, 1976
• Sphaerium bequaerti (Dautzenberg & Germain, 1914)
• Sphaerium corneum (Linnaeus, 1758) – European fingernail clam
• Sphaerium lacustre (O. F. Müller, 1774)
• Sphaerium nitidum Clessin, 1876 – Arctic fingernail clam
• Sphaerium novaezelandiae Deshayes, 1855
• Sphaerium nucleus (Studer, 1820)
• Sphaerium ovale (A. Férussac, 1807)
• Sphaerium rhomboideum (Say, 1822)
• Sphaerium rivicola (Lamarck, 1818)
• Sphaerium solidum (Normand, 1844)
• Sphaerium stuhlmanni E. von Martens, 1897
• Sphaerium transversum (Say, 1829)