The Asian Clam is a freshwater bivalve mollusc from Asia.
It has been introduced into numerous parts of the world, including North America and Europe.
Throughout the breeding cycle, about up to 350/2,000 juveniles are released every day.
They are mature between one and four years and at this time, are about 1 centimetre long.
The adults can reach up to 5 centimetres long.
Curbicula fluminea is a competitive species that can replace the already threatened native clams.
Probably imported as a food sources, the large colonies can clog waterways and pipes.
It is usually found in in lakes and streams with sand, mud and gravel substrates.
The pictures below show this invasive species in a lake in SW France.