Triangle floater

Alasmidonta undulata

NH Conservation Status: Not listed

NH State Rank Status: Apparently secure (global – apparently secure)

Distribution: All major watersheds in NH.

Description: A medium sized mussel up to 3 inches with a “chunky” appearance. Shell color is generally a mix of greenish-brown or yellow. The inner shell (nacre) is pinkish or bluish-white. The foot is usually white.

Commonly Confused Species: Dwarf wedgemussel, brook floater, creeper

Habitat: Most commonly in rivers and streams with gravely substrates. Less common in lakes and ponds.

Life History: Uses a range of host fish including the common shiner, white sucker, and large-mouth bass.

Conservation Threats: Triangle floaters can tolerate non-flowing water so it is less sensitive to the effects of dams compared with many other freshwater mussels of the Alasmidonta genus (e.g., brook floaters, dwarf wedgemussels). As a filter feeder, like many other freshwater mussels, they are likely sensitive to pollution and habitat degredation.