Los Tuxtlas Biosphere Reserve

Los Tuxtlas Biosphere Reserve, the northernmost tropical rainforest in Mesoamerica, boasts the highest density of endemic plant species in Mexico, with over 500 endemics per 1,000 square kilometers. It is a vital refuge for howler monkeys in eastern Mexico, where their population density is 20% higher than in #8 Tehuacán-Cuicatlán. The reserve's three volcanic lakes—Catemaco, Chalchoapan, and Sontecomapan—support 50% more lacustrine species than the Mexican average, creating unique freshwater ecosystems. This hotspot is a biodiversity fortress.