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Mississippi National River and Recreation AreaA bridge spans the Mississippi River between wooded shores.
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Mississippi National River and Recreation Area
Elktoe
(Alasmidonta marginata) Say, 1818
A Elktoe mussel
K.S. Cummings, Illinois Natural History Survey
Other Common Names:
None.
Habitat:
Medium-sized streams in gravel or mixed sand and gravel.
Length:
Up to 4 inches (10.2 cm).
Outer Shell Color:
Yellow or green shell with interrupted bright green rays, and in some cases small green spots.
Inner Shell Color:
Bluish white, sometimes salmon pink near the shell ends.
Shell Thickness:
Thin.
Shell Outline:
Shell is longer than wide. An outline of the entire shell is nearly, but not perfectly, triangular (imagine a triangle blown up, like a balloon). A distinct beak forms the top of the triangle (just above the point where the 2 shell halves join).
Shell Surface:
Looks somewhat swollen. Running your finger along the outer shell surface from the beak straight to the blunt point, you will feel a distinct edge, with ridges. The rest of the outer surface is smooth and dull.
Scientific Description:
Elongate, subrectangular, Inflated, sexes alike. Posterior slope with ridges. Posterior ridge sharp.
Similar Looking Mussels:
Host Fish:
Rock Bass, Whitesucker, Northern Hog Sucker, Warmouth, Shorthead Redhorse
Distribution:
Widespread but spardic in distribution.
Minnesota State Listing:
Threatened.
Federal Listing:
None.
Coon Rapids Dam  

Did You Know?
Over 600 men worked around the clock using hand tools, horses and coal powered shovels to build the original Coon Rapids Dam in 1913. The dam was rebuilt between 1995 and 1997.

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Last Updated: September 25, 2006 at 09:58 EST