This species has apparently never been found in large numbers and has been reported as rare and endangered since the early 1970s. The total population has been estimated at 100000 mature individuals. At a historical mussel shell excavation site near the Verdigris River, the Neosho Mucket was rarely encountered among all uncovered shells; and its rare occurrence closely matched its rarity in the modern Verdigris River. This suggests that populations in the Verdigris have long been sparse; and if the Neosho mucket is generally a naturally rare species despite evidence from relic shells of a previously larger overall geographic range, this may explain its apparent vulnerability to local extirpation.