Semideciduous tropical rain forest
(10-15 meters canopy)

This is a biologically-rich tropical forest dominated by trees up to 15 m. in height, with many different species of shrubs, herbs, climbing plants, lianas and epiphytes. It is a forest that has been continuously disturbed since remote times, by humans, hurricanes and fire. Among the most notable abundant trees we have found the following: the "chicle tree" (Manilkara zapota), the chacá (Bursera simaruba), tropical cedar (Cedrela mexicana), and ramón (Brosimum alicastrum), among many others. This forest is the habitat of the spider monkey, jaguar, and many other notable vertebrates. A new wild species of Vanilla has been found in this forest and is under study.

Secondary semideciduous forest
(7-10 meters canopy)

This is the most common ecosystem in the non-flooded soils. It is a second-growth vegetation originated by natural (hurricanes) or human (agriculture and forest fires) perturbation of the tropical forests.

Seasonnally innundated forest

These are forest of lesser height (up to 12 m. tall) dominated by the logwood known locally as "tinto" (Haematoxylon campechianum). This forest is poorer in tree species than the semideciduous forest. Some notable tree species are: the black chechem (Metopium brownei), yaxnique (Vitex gaumeri), and a wild relative of the coca tree (Erythroxylon campechianum), among many others. This ecosystem has been very poorly studied. A possible new variety of Manilkara zapota that grows in these swamps is under study.

Palm grove

In this ecosystem endemic palm species dominate the landscape, such as the “Kuká” (Pseudophoenix sargentii), the “Nakax” (Coccothrinax readii) and the
“Xiat” (Chamaedora seifrizii).

The reserve has the largest protected natural savanna known in Mexico. It is a grassland with many small scattered trees that becomes flooded 3-4 months a year. The dominant families are Gramineae and Cyperaceae. The most notable tree species are: the “nanche” (Byrsonima crassifolia), the calabash tree or "jícaro" (Crescentia cujete), and the tasiste palm (Paurotis wrightii).


Other wetlands

The area has many different kinds of wetlands. The different types result from the length of time that they are flooded: from a permanently waterlogged state to inundation for only a few months a year at the most. The different types are recognized by the dominant vascular plant species, such as the tular or cattail marsh dominated by Typha latifolia; the sawgrass marshes dominated by Cladium jamaiscense and the permanent water bodies dominated by Nymphaea spp. A possible new genus of a nitrogen fixing algae has been discovered in the periphyton that develops in this ecosystem in the rainy season.


These are small or large permanent water bodies that formed crevices and sinkholes on the rocky limestone outcrops of the region. They form a complex network of underground crevices and tunnels with occasional windows to the outside. These ecosystems are almost unknown and a great diversity of aquatic life exists in them: fish, crustacean, protozoa, diatoms, algae, etc.