• Mississippi National River and Recreation Area

    Mississippi

    National River & Recreation Area Minnesota

White Heelsplitter

(Lasmigona complanata) Barnes, 1823f
A White Heelsplitter mussel
K.S. Cummings, Illinois Natural History Survey
Other Common Names:
Pancake; Razorback; Elephant-ear; Hackle-back.
Habitat:
Pools or sluggish streams with a mud, sand, or fine gravel bottom.
Length:
Up to 8 inches (20.3 cm).
Outer Shell Color:
Dark brown or black shell.
Inner Shell Color:
Bluish white or white, with some iridescent coloring on one end of the shell.
Shell Thickness:
Relatively thin. Very thin in young mussels.
Shell Outline:
The entire shell outline is shaped somewhat like an equal-sided triangle that has been blown-up, like a balloon. An extension of the shell resembling a large, flat triangular wing makes up one "corner" of the entire shell outline. Imagining the shell without a wing, the shell shape is somewhat egg-shaped, but the edge that meets with the wing is straight.
Shell Surface:
Outer shell surface is flat and smooth, except for some low wavy ridges on the wing, and two distinct low ridges that run in a straight line from the beak, separating the triangular wing from the shell body.
Scientific Description:
Very compressed brown or black shell. Large posterior ala. Beak sculptured with two diverging rows of tubercles extending onto disc as shallow ridges on posterior slope. Sexes alike. Postbasal mantle margin narrow, simple. Homogeneous marsupium.
Similar Looking Mussels:
Host Fish:
Common Carp, Green Sunfish, Largemouth Bass, White Crappie, Orangespotted Sunfish, Banded Killifish
Distribution:
Widespread and common.
Minnesota State Listing:
None.
Federal Listing:
None.

Did You Know?

Lock and Dam Number 1 from a long distance.

At Lake Itasca, the elevation of the Mississippi River is 1,475 feet above sea level. It drops to sea level at the Gulf of Mexico. More than half of that drop occurs within the state of Minnesota.