Patterns of fish species richness in rivers of the central region of Argentina.

BISTONI, M. A.; HUED, A. C.

BRAZILIAN JOURNAL OF BIOLOGY

Lugar: Sao Paulo, Brasil; Año: 2002 vol. 62 p. 1 - 12

1519-6984

The knowledge of the fish fauna of the rivers in the central part of Argentina has increased in the last few years. However, fish community distribution is still unknown. We analyzed the variation of fish species richness and trophic structure along an upstream-downstream gradient and identified the factors associated with the patterns observed. The fish community composition varied along a headwater-downstream gradient. Species richness and trophic structure were correlated significantly with altitude, order and distance from source. Headwater communities showed a simple structure. From these zones to downstream areas fish communities changed because of the addition of other fish species.