List of ecoregions in Mexico

The following is a list of ecoregions in Mexico as identified by the World Wide Fund for Nature (WWF). A different system of ecoregional analysis is used by the Commission for Environmental Cooperation, a trilateral body linking Mexican, Canadian and United States environmental regime.

Terrestrial ecoregions
The terrestrial ecoregions of Mexico span two biogeographic realms - the Nearctic and Neotropic - which together constitute the entire biogeography of the Americas.

Veracruz is the most biodiverse state with 10 ecoregions across 5 biomes and 2 realms. Chiapas comes in a close second with 10 ecoregions across 4 biomes in the same realm. By contrast, Morelos is the least biodiverse state with just 2 ecoregions.

Baja California Complex

 * Baja California

Colorado River Complex

 * Colorado Delta
 * Sonoran

Sinaloan Coastal Complex

 * Sinaloan Coastal

Rio Bravo Complex

 * Rio Bravo
 * Pecos
 * Guzman
 * Mapimí
 * Cuatro Ciénegas
 * Llanos El Salado
 * Conchos
 * Lower Rio Bravo
 * Rio San Juan
 * Rio Salado

Lerma/Santiago Complex

 * Santiago
 * Chapala
 * Lerma
 * Rio Verde Headwaters
 * Manantlan/Ameca

Rio Panuco Complex

 * Rio Panuco

Balsas Complex

 * Balsas

Pacific Central Complex

 * Tehuantepec

Atlantic Central Complex

 * Southern Veracruz
 * Belizean Lowlands
 * Catemaco
 * Coatzacoalcos
 * Grijalva-Usumacinta
 * Yucatán

Warm Temperate Northeast Pacific

 * Southern California Bight
 * Cortezian
 * Magdalena Transition

Tropical East Pacific

 * Revillagigedos
 * Mexican Tropical Pacific
 * [ Clipperton ] (an overseas possession of France, disputed by Mexico)
 * Chiapas-Nicaragua

Warm Temperate Northwest Atlantic

 * Northern Gulf of Mexico

Tropical Northwestern Atlantic

 * Southern Gulf of Mexico
 * Western Caribbean