Genus of bivalves
Elliptio dilatata museum specimenElliptio is a genus of medium- to large-sized freshwater mussels, aquatic bivalve mollusks in the family Unionidae ,[1] [2] commonly known as the unionids, freshwater mussels or naiads .
In contrast with many other groups of American Unionidae, the Elliptio species reach their greatest diversity in the Atlantic-draining rivers of Georgia and the Carolinas, and large parts of Florida. One species ranges north into New England and southern Canada, and two occur in the interior Mississippi drainages. Most Elliptio species have elongated shells, with silvery or purplish interior nacre beneath a thick periostracum , and few reach large size or thickness.
The genus name Elliptio refers to the elliptical shape of these bivalves.
As of 2023 there are 43 species in the genus.[2]
Species
The following species are recognised in the genus Elliptio :
Elliptio ahenea (I. Lea, 1843)
†Elliptio albertensis (Whiteaves, 1885)
Elliptio angustata (I. Lea, 1831) – Carolina lance
Elliptio arca (Conrad, 1834) – Alabama spike
Elliptio arctata (Conrad, 1834)
Elliptio chipolaensis (B. Walker, 1905) – Chipola slabshell
Elliptio cistellaeformis (I. Lea, 1863)
†Elliptio clinopisthus (C. A. White, 1882)
Elliptio complanata ([Lightfoot], 1786) – Eastern elliptio
Elliptio congaraea (I. Lea, 1831)
†Elliptio cornelliana (Maury, 1902)
Elliptio crassidens (Lamarck, 1819) – Elephantear
Elliptio dariensis (I. Lea, 1842)
Elliptio downiei (I. Lea, 1858) – Satilla elephantear
Elliptio fisheriana (I. Lea, 1838)
Elliptio folliculata (I. Lea, 1838) – pod lance
Elliptio fraterna (I. Lea, 1852) – brother spike
Elliptio fumata (I. Lea, 1857)
†Elliptio haydeni (Meek, 1860)
†Elliptio hoelzli Modell, 1943
Elliptio hopetonensis (I. Lea, 1838) – Altamaha slabshell
†Elliptio hubbardii (Gabb, 1869)
Elliptio icterina (Conrad, 1834) – variable spike
Elliptio jayensis (I. Lea, 1838)
Elliptio judithae A. H. Clarke, 1986
Elliptio lanceolata (I. Lea, 1827) – yellow lance
†Elliptio larteti (Noulet, 1846)
Elliptio marsupiobesa Fuller, 1972
Elliptio mcmichaeli Clench & R. D. Turner, 1956 – fluted elephantear
Elliptio monroensis (I. Lea, 1843)
†Elliptio mormonum La Rocque, 1960
†Elliptio nanaimoensis (Whiteaves, 1901)
Elliptio nasutidus (I. Lea, 1863)
Elliptio nigella (I. Lea, 1852) – recovery pearly mussel, winged spike
Elliptio occulta (I. Lea, 1843)
†Elliptio pachyodon Pilsbry, 1953
Elliptio producta (Conrad, 1836) – Atlantic spike
Elliptio pullata (I. Lea, 1857)
Elliptio purpurella (I. Lea, 1857)
Elliptio roanokensis (I. Lea, 1838) – Roanoke slabshell
†Elliptio salissiensis L. S. Russell, 1952
Elliptio shepardiana (I. Lea, 1834) – Altamaha lance
Elliptio spinosa (I. Lea, 1836) – Altamaha spinymussel, Georgia spinymussel
†Elliptio washakiensis (Meek, 1871)