First record ofcylindrospermopsis raciborskii(Woloszynska) Seenayya et Subba Raju (Cyanobacteria) in a lotic system in France

Cylindrospermopsis raciborskii (Woloszynska) Seenayya et Subba Raju, a potentially toxic bloom forming cyanobacteria (Nostocales), was recorded in the River Seine in August 2001. The cyanobacterium was previously observed in some French ponds but this is the first report of this reputedly tropical species in a river in France.