This study examines the richness of phytoplanktonic species found in one aquifers Lagunas de Zempoala National Park. The samples were carried out monthly from September 2018 to February 2019. During this period, 26 integrated seven divisions, 20 families and classes recognized, among which Bacillariophyceae class stands with greatest diversity (eight species). Staurastrum bulbosum was most freq...