Boundaries

This ecoregion is located along the Caribbean coast of Central America from the Yucatán Peninsula south to the Mutagua River at the Gulf of Honduras. In Mexico it encompasses the southern half of Quintana Roo, the western edge of Campeche, and a small area in eastern Yucatán. It also covers the entire country of Belize, eastern Guatemala, and the western edge of Honduras.

Topography

The topography of the ecoregion is primarily flat along the coast and hilly to mountainous in the Sierra Madre. The highest peak in the ecoregion occurs in the Sierra de los Cuchumatanes at elevations that exceed 3200 m. The Maya Mountains are an isolated mountain range located in eastern Belize.

Freshwater habitats

The northern part of the ecoregion is a transition from the cenote-rich area in the northern Yucatán Peninsula to the small surface basins characteristic of southeastern Quintana-Roo. This area contains some springs and Bacalar Lagoon, a large freshwater lagoon where there is a mix of freshwater and marine forms. Belize is also characterized by numerous lagoons, as well as rivers and wetlands.

Terrestrial habitats

The terrestrial habitats in the ecoregion include mangroves along the coast, and Yucatán moist forest, Petén-Veracruz moist forests, and Central American Atlantic moist forests along the coastal plain. Pockets of Belizian pine forests occur in pre-montane areas in Belize. Higher elevations in the ecoregion are dominated by Central American montane forests, Motagua Valley thornscrub, Sierra Madre pine-oak forests, and a small area of Central American dry forests.

Description of endemic fishes

Some of the ecoregion’s endemics include Amphilophus margaritifer, chisel-tooth cichlid (Cichlasoma bocourti), mountain molly (Poecilia teresae), and southern checkmark cichlid (Vieja godmanni). Potamarius izabalensis and Archocentrus spinosissimus are endemic to Lago de Izabal, and Hyphessobrycon milleri and Vieja microphthalma are endemic to the Motagua River basin.

Other noteworthy fishes

The ecoregion’s karst-derived subterranean habitats support a number of unusual species, such as the blind swamp eel (Ophisternon infernale). The freshwater croaker Aplodinotus grunniens (Sciaenidae) reaches its southern limit here. The Yucatan pupfish (Cyprinodon artifrons), ocellated killifish (Floridichthys polyommus), and Yucatan flagfish (Garmanella pulchra) reach their southern limit in Central America in the region.

Ecological phenomena

There has been penetration of tropical fauna toward the impoverished Yucatán ecoregion.

Justification for delineation

Ecoregion delineations were based on qualitative similarity/dissimilarity assessments of major basins, using the standard administrative hydrographical regions of the Mexican federal government. The vast majority of the species/families within this ecoregion are Neotropical. The ecoregion delineation was based on the distributions of the Neotropical species (cichlids mainly).

Level of taxonomic exploration

Excellent within Quintana Roo.