They are endemic to North America, and are mainly found in the Midwest and southeastern United States as well as Ontario, Canada.

Members of this genus are long-term brooders and hold their eggs over winter.

[1] Species of this genus package their larvae, known as glochidia, in conglutinates that resemble prey items such as aquatic insects, fish fry, or fish eggs.

The lures are intended to attract fish that the glochidia can use as hosts during development.

When squeezed, the conglutinate will rupture, allowing the larvae to parasitically attach to the fish.