(Lampsilis siliquoidea) Barnes, 1823
Male and Female Fat Muckets

K.S. Cummings, Illinois Natural History Survey

Other Common Names:
Lake Pepin mucket; Grass mucket; Pugnose mucket.
Lakes and small to medium-sized streams in mud, sand, or gravel.
Up to 5 inches (12.7 cm).
Outer Shell Color:
Yellow or brown shell, darker as adult, usually with green rays.
Inner Shell Color:
White or bluish white with iridescent coloring on the widest end of the shell.
Shell Thickness:
Shell Outline:
Shell outline is longer than wide. The shell edge that is directly opposite the beak (located slightly above the point where the 2 shell halves join) is usually straight. The end of the shell farthest from the beak comes to a slightly rounded point in males, but looks cut off in females. In both males and females, this end is the widest point of the shell. It is wider in females than in males.
Shell Surface:
The outer shell looks very swollen or bulged out, especially in females (swollen mostly towards the widest end of the shell).
Scientific Description:
Moderately elongate and very inflated, especially female. Female generally more postbasally inflated and rounded. Postbasal mantle margin broad, especially female, variably pigmented and papillose (outer surface often minutely papillose). Female has mantle flap, atypical of Lampsilis. Heterogenous marsupium.
Similar Looking Mussels:
Host Fish:
Bluegill, Largemouth Bass, Yellow Perch, Walleye, Black Crappie
Widespread and common throughout the Midwest.
Minnesota State Listing:
Federal Listing:

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