Who is the Giant Pearl Mussel ?

 

Presentation of the Giant Pearl Mussel : Margaritifera auricularia


The Giant Pearl Mussel, scientifically named Margaritifera auricularia is the biggest freshwater mussel in Europe and can reach up to 20 cm (usually 15 to 18 cm). It can weigh up to 500 grams and live to 150 years.

It is distinguished by a shell recessed on the ventral side, which gives it a form of human ear, hence its name Margaritifera auricularia. The Giant Pearl Mussel lives in great rivers, in rocky or gravelly funds.

Historically widespread throughout Western Europe, the number of specimens found in European rivers has fallen drastically over the past two centuries.


Distribution

Thought disappeared for nearly a century, the Giant Pearl Mussel was finally rediscovered in 1998 in Vienna and Creuse and then in other rivers.

Margarifera Auricularia is now critically endangered and can only be found in the Creuse, the Vienna, and the Charente rivers, as well as the South West of France : the Dronne, the Luy and the Salve. At a European level, the Giant Pearl Mussel can be found in the Ebro basin in Spain. Other populations may still exist in other rivers but are not yet rediscovered. An action of the project is the prospection and research of new populations of Giant Pearl Mussel.
 
 
Actual distribution (red points for living animals) et recent one (orange points for shells) of the Giant Pearl Mussel in France. (credit : Prié, 2018).
orange : coquilles retrouvées rouge : individus vivants
 

Rivers prospected (grey lines) et  prospection sites by the technical of DNA environnemental (red points ) in France the last decade (credit : Prié, 2018).

 
Fossil distribution (cross) and historical (blue points and blue lines) of the Giant Peal Mussel from litterature and museums datas. (credit : Prié, 2018).