(Lasmigona costata) Rafinesque, 1820
A Fluted-Shell mussel

K.S. Cummings, Illinois Natural History Survey

Other Common Names:
Sand mussel, squawfoot.
Lives in sand, mud, or fine gravel in medium to large rivers where the flow of water are slow to moderate.
Up to 7 inches (17.8 cm).
Outer Shell Color:
Green to yellowish brown in younger individuals and becomes chestnut or dark brown as the shell matures.
Inner Shell Color:
White, bluish white, and often salmon-colored.
Shell Thickness:
Moderately thick.
Shell Outline:
Longer than wide and slightly inflated. Both the two ends of the mussel are sharply curved. The top and bottom are also both straight to slightly curved.
Shell Surface:
Shell is smooth on end closest to where the two halves meet and contains noticeable ridges on the opposite end.
Scientific Description:
Yellow, green, or brown shell often with green rays. Shell elongate, subrectangular and compressed. Ridges or "flutes" on posterior scope.
Similar Looking Mussels:
Host Fish:
Widespread but relatively uncommon.
Minnesota State Listing:
Special Concern
Federal Listing:

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