A new basin, a new river, a new home - the introduction of Limnoperna fortunei (Dunker, 1857) in Paraiba do Sul basin and its potential consequences to the most important basin for water supply in Southeast Brazil

The golden mussel Limnoperna fortunei is native to Southeast Asia but is now widespread in South America. Limnoperna fortunei is an ecosystem engineer able to change the environment, and also directly affect the native species. Golden mussel grows attached to hard natural and artificial substrata in dense agglomerates, up to 150,000 ind m-2. The main goal of this paper is to report the invasion of the golden mussel Limnoperna fortunei in the Paraiba do Sul River (southeast Brazil), with emphasis on its major introduction vectors and pathways. In addition, the potential ecological and economic consequences of golden mussel spread across this river basin were also addressed. Our study reports the occurrence of the golden mussel in Santa Branca Reservoir (S & atilde;o Paulo, Brazil), inserted in the Paraiba do Sul River basin. This basin is important to agriculture and industrial activities, as well as water supply, for several municipalities across the basin. Moreover, this basin is responsible for a large part of the water used in the Metropolitan area of Rio de Janeiro, where live more than eight million people. The spread of this species throughout this basin may have disastrous consequences for native fauna and humans that depend on the Paraiba do Sul waters.