Margaritifera hembeli
CR

Margaritifera hembeli

Declining

Photo: Wikimedia Commons (CC) via https://en.wikipedia.org/wiki/Louisiana_pearlshell

Overview

The Louisiana pearlshell, Margaritifera hembeli, is a rare species of bivalve mollusk in the family Margaritiferidae. This freshwater mussel is native to Louisiana in the United States, and was previously present also in Arkansas. 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.

Its life cycle involves a stage where it lives parasitically inside a fish. This mollusk is sensitive to increased sedimentation and cannot tolerate impoundments. Because of its limited range and its population decline, the International Union for Conservation of Nature has rated this mollusk as being critically endangered.

Margaritifera hembeli faces severe population decline due to habitat degradation from agricultural runoff and sedimentation in its freshwater mussel beds. Dam construction and water diversions have altered natural flow regimes essential for its reproductive cycle, while invasive species compete for resources and disrupt established ecological relationships. The species' extremely limited range makes it particularly vulnerable to localized environmental changes.

Threat summary

Habitat

This freshwater pearl mussel inhabits clean, well-oxygenated streams and rivers with sandy or gravelly substrates. It requires stable water conditions and specific host fish species for its larval development stage.

Wetlands (inland) - Permanent rivers/streams· major

Conservation measures underway

Species managementSpecies recoverySpecies reintroductionEx-situ conservationLegislation

Other threatened species in MARGARITIFERIDAE

CR

Pseudunio marocanus

Declining
CR

Gibbosula crassa

Declining
Freshwater Pearl MusselEN

Freshwater Pearl Mussel

Margaritifera margaritifera

Declining
CR

Spengler's Freshwater Mussel

Pseudunio auricularius

Declining

Threatened in United States

VU

Lepiota echinella

Unknown
VU

Paddlefish

Polyodon spathula

Unknown
VU

Copper Shark

Carcharhinus brachyurus

Declining
EN

Lyophyllum deliberatum

Unknown

Frequently asked questions

Why is Margaritifera hembeli classified as Critically Endangered?
Margaritifera hembeli is classified as Critically Endangered — facing an extremely high risk of extinction in the wild — because population sizes are very small, declining sharply, or restricted to a tiny range. Margaritifera hembeli faces severe population decline due to habitat degradation from agricultural runoff and sedimentation in its freshwater mussel beds. Dam construction and water diversions have altered natural flow regimes essential for its reproductive cycle, while invasive species compete for resources and disrupt established ecological relationships. The species' extremely limited range makes it particularly vulnerable to localized environmental changes.
Where does Margaritifera hembeli live?
Margaritifera hembeli occurs in United States. Country-level distribution data is sourced from the IUCN Red List and cross-referenced with GBIF occurrences.
What are the main threats to Margaritifera hembeli?
The main threats to Margaritifera hembeli are 1.1, 11.4, 2.3, and 3.2. The full IUCN-classified threat record for this species is detailed on the species page.

Get weekly conservation intelligence

One short digest a week of the most striking species and country data we ship, plus breaking conservation news paired with our database where it matters.

Free, no spam. One-click unsubscribe in every email.