• Mississippi National River and Recreation Area


    National River & Recreation Area Minnesota

Fragile Papershell

(Leptodea fragilis) Rafinesque, 1820
A Fragile Papershell mussel
U.S. Army Corps of Engineers
Other Common Names:
Papershell; Cottonmouth
Streams of all sizes in mud, sand, or gravel.
Up to 6 inches (15.2 cm).
Outer Shell Color:
Yellow to tan or green, usually with many faint green rays (however, some are rayless).
Inner Shell Color:
Pinkish white or pink and highly iridescent.
Shell Thickness:
Shell Outline:
Somewhat longer that wide. On either side of the point where the two shell halves join, there may be a flattened extension of the shell that resembles a wing. From the beak (the beak is the point above where the two shell halves join), the longest end of the shell from the beak has the largest wing, but its size may be much smaller or completely missing in adult mussels. A smaller second wing extending from the shortest end of the shell from the beak may only be visible in young mussels
Shell Surface:
Outer shell surface may be rough and dull, or smooth and shiny. The entire shell looks swollen, especially for female mussels. The beak is flat and barely visible.
Scientific Description:
Shell yellow or green, usually with green rays. Rough, dull finish. Bialate, with minimal anterior ala. Slightly inflated shell (female more so).
Similar Looking Mussels:
Pink papershell, Narrow Papershel.
Host Fish:
Freshwater drum.
Widespread and common
Minnesota State Listing:
Federal Listing:

Did You Know?

A slow and shallow section of Itaska.

At the headwaters of the Mississippi, the average surface speed of the water is 1.2 miles per hour. People typically walk 3 miles per hour.