FIG. 1.

Cuatro Ciénegas Coahuila microbial diversity at the phylum level in different sites within the valley. The taxonomy was obtained using environmental DNA and 16S rDNA gene as marker. The numbers refer to different samples within the region. CH (Churince), RM (Río Mesquites, a site with desiccation pools and a river with oncolites), ES (Escobedo), LH (Los Hundidos region, with the Poza Roja), PA (Pozas Azules ranch, with the sites Poza Azul II and Green Mat), MR (a mine shaft where a sample was obtained 600 m below the surface). The map of Mexico shows the CCB site in the state of Coahuila. The photographs correspond to CCB sites.