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Biogeographic delimitation of the Amazon Ecoregion. A - Amazon basin studied, delimited by (WWF 2019). The yellow dots are occurrences of amphibians; B - Location of the 52 hydrographic sub-basins and the 30 rivers that drain the most water in the Amazon region. The name of each sub-basin is based on its main tributary river (see Suppl. material 1) .
