Louisiana pearlshell

It grows to a length of about 10 cm (4 in) and lives on the sand or gravel stream-bed in riffles and fast flowing stretches of small streams.

Because of its limited range and its population decline, the International Union for Conservation of Nature has rated this mollusk as being "critically endangered".

[7] When it was first placed on the Endangered Species List in 1988 the mussel was thought to remain only in the Bayou Boeuf river system in Rapides Parish, Louisiana.

Some areas, including streams in the Kisatchie National Forest, undergo increased sedimentation from nearby silviculture, road maintenance, and livestock grazing.

[9] Because it is restricted to only two river drainages in central Louisiana, and declined by over 80% during the last few decades, the International Union for Conservation of Nature has rated this mollusk as being "critically endangered".