Snuffbox
Epioblasma triquetra (Raf.)

Status: State Endangered (August 1, 1989).

Occurence: Occurs in the Embarrass, St.Croix, Wolf, and Little Wolf Rivers.

Aid to ID: Thick, triangular shell with a sharply defined, broadly expanded posterior slope. Epidermis yellow or yellowish-green with green rays, blotches or chevron markings. Males are triangular while females are somewhat elongate. The anterior end is rounded, and the posterior end is truncated in males, but expanded in females. The beak sculpture has three or four faint, double-looped bars. The beak cavity is fairly deep and the nacre is pearly white. 2.5 inches (6.4 cm) long.

Habitat: Inhabits medium to large, clear rivers in gravel riffles.

Management Considerations: Habitat destruction and river pollution have resulted in mussel declines. Protection of habitat and improvements in water quality along with restriction of dredging, impoundments, sand and gravel mining, and navigational improvements would benefit this species. The development of fish runways to facilitate the movement of host species through or around dams would also help to protect the snuffbox.

The content for this page was originally presented in the Endangered and Threatened Invertebrates of Wisconsin, a free publication available by contacting the Endangered Resources Program.