Genus Corbicula main content.

Genus Corbicula

Family Corbiculidae

Species Summary


Our only representative of the family Corbiculidae is the invasive species Corbicula fluminea (Muller, 1774), the asiatic clam. Although widely distributed in the US, C. fluminea is limited in the NY metro area to several lakes on Long Island, NY, and to Twin Lakes, CT, and in NJ is present in all major waterways outside the Pine Barrens.

Species Summaries

Species Summary

Corbicula fluminea (Muller, 1774)
asiatic clam



size: 50mm, though typically smaller
beak: situated centrally, and highly placed above the hinge line
color patterns: distinguished by three brown or purple radial color bands near the umbos; periostracum brown or blackish brown; nacre colored white and purple
shape: inflated, triangular, or rounded triangular in older specimens
shell features: posterior external hinge ligament, with many coarse concentric ribs on epidermis
teeth: long, finely serrated laterals, two in the right valve and one in the left; pseudocardinals short, strong, with blunt surfaces, three per valve


abundance: uncommon
status: reportedly in decline; US, NY, NJ, CT: not legally protected
conservation challenges: presence of this invasive species should be sought in New Jersey and Connecticut


N.A. distribution: nearly all major eastern and midwestern river systems; Connecticut west to Minnesota and Iowa, south to Georgia, Oklahoma and Louisiana
present metro distribution: confined to several lakes on Long Island, NY
regional distribution: NY: all major watersheds except the upper Delaware River watershed; NJ: all major watersheds outside the Pine Barrens; CT: Connecticut, Housatonic, Thames River and South central coast watersheds; East Twin Lakes (Housatonic River watershed)

A map of the counties in the Pennsylvania, New York, and New Jersey areas with orange colors indicating Asiatic clam distribution.

Life History:

habitat: large rivers, canals and lakes on any hard substrate; some tolerance to salinity; limited tolerance to low calcium and acidity Habitat Photo
hosts: no host required; free-swimming veliger larvae



C. fluminea

Left view
Left view
Right view
right view
Ventral view
ventral view
Profile view
profile view
nacre with bluish cast
Long fine laterals
long, fine laterals; 2 right, 1 left pseudocardinals short, 3 per valve
Concentric ribs
many concentric ribs