Resumo

AGUILAR-AGUILAR, Rogelio  e  SALGADO-MALDONADO, Guillermo. Diversity of freshwater fishes parasitic helminths in two Mexican hydrological basins: Helminths and the hypothesis of the betadiverse Mexico. INCI [online]. 2006, vol.31, n.7, pp.484-490. ISSN 0378-1844.

A diversity analysis of helminth parasites of freshwater fishes in different geographic units from two of the most important Mexican hydrological basins, Río Lerma and Río Papaloapan, was undertaken in order to establish the rate of change in species diversity among these geographic units, and to detect the contribution of each region to the hypothesis of betadiverse Mexico. A grid cell of 0.5×0.5º was superimposed on each hydrological basin. Only those grid squares with at least one record of helminth parasites of freshwater fishes were included. Based on the species richness for grid square, beta diversity was calculated according to the formula β= S_γ/S_α. In addition, a complementarity analysis was applied in order to establish the differences between grid squares and also between hydrological basins, in relation to species composition. The total of helminth species was included in nine grid squares, five located in the Papaloapan basin and four in the Lerma basin. The complementarity areas obtained can be considered as relevant for conservation because in these grid squares are located some localities with adequate environmental conditions that permit the development of the complex life cycles of most of the organisms selected for this work.

Palavras-chave : Diversidad ; Helmintos Parásitos ; Peces Dulceacuícolas ; Río Lerma ; Río Papaloapan.