Endangered Species
Midwest Region



Map of the eight states in the Midwest Region: Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri, Ohio and Wisconsin.

The Midwest Region includes Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri, Ohio and Wisconsin. Find a location near you


Endangered Species Program

Conserving and restoring threatened and endangered species and their ecosystems


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Snuffbox (Epioblasma triquetra)

Status: Endangered

Snuffbox mussel. Photo by G. Thomas Watters; Ohio State University

The population of the snuffbox mussel, in terms of range and numbers, appears to have declined by at least 90 percent.

Photo by G. Thomas Watters, Ohio State University


Status: Endangered, listed February 14, 2012 Adobe PDF Icon


Habitat: Medium to large rivers in mud, sand, or gravel


Lead Region: 3


Region 3 Lead Office: Twin Cities Field Office


Range: Arkansas, Minnesota, Missouri, Oklahoma, Wisconsin


The snuffbox is a small, triangular freshwater mussel that is found in Alabama, Arkansas, Illinois, Indiana, Kentucky, Michigan, Minnesota, Missouri, Ohio, Pennsylvania, Tennessee, Virginia, West Virginia, and Wisconsin. It lives in small to medium-sized creeks in areas with a swift current, although it is also found in Lake Erie and some larger rivers.



5-Year Review Adobe PDF Icon


Endangered Listing Rule


News Release (Feb. 13, 2012): U.S. Fish and Wildlife Service Lists Two Freshwater Mussels as Endangered Species


Federal Register Final Rule: Endangered and Threatened Wildlife and Plants; Listing the Rayed Bean and Snuffbox as Endangered (Feb. 14, 2012)


Questions and Answers: Rayed Bean and Snuffbox Mussels Listed as Endangered (Feb. 2012)


Snuffbox Fact Sheet (Feb. 2012)


Information about the Rayed Bean


Links to Additional Information

Michigan Natural Features Inventory Abstract (2-page PDF)


Dr. Chris Barnhart's Unio Gallery - includes photos and video



Midwest Endangered Species Home



Last updated: February 25, 2019