Boundaries

This ecoregion extends from Punta Chame in Panama (western boundary of the Río Capira) to the Río Tuira drainage in the northeast. The ecoregion also includes the Archipiélago de la Perlas in the Golfo de Panamá.

Topography

Hills less than 600 m cover much of the western portion of the ecoregion, whereas mountains of the Sierranía del Darién border the northeastern edge. The Bayano and Chucunaque rivers drain in depression terrains (MINSA 2007).

Freshwater habitats

The freshwater habitats of this ecoregion include brackish to freshwater marshes and swamps, mangroves, rivers, and streams. Some of the larger areas of coastal mangroves and mudflats include Chame Bay, the mouths of the ríos Tapia and Pacora, the lower Río Bayano, the mouths of the ríos Juan Díaz and Tocumen, and along the coast toward Río La Maestra. Freshwater wetlands occur at Tocumen marsh, La Jagua, and the Chimán wetlands, which also includes extensive mudflats and coastal mangroves. The estuaries on the north and eastern side of the Golfo de San Miguel also contain extensive tidal mudflats and mangroves, including those around the Congo and Cucunatí, the mouth of the Río Sambú, and in the Punta Patiño Reserve (Angehr 2005).

Lake Bayano is a reservoir formed by the damming of the Río Bayano (Chepo). The lake has since become one of the most important freshwater habitats in eastern Panama.

Terrestrial habitats

Wet and humid lowland forest is the dominant vegetation type throughout much of the ecoregion (Stattersfield et al. 1998). The terrestrial ecoregions that comprise these moist forests include the Isthmian-Atlantic moist forests and South American Pacific mangroves that flank the Bahía de Panamá and Golfo de San Miguel, and the Chocó-Darién moist forests that border the northern and eastern side of the ecoregion. Eastern Panamanian montane forests occupy higher elevations (World Wildlife Fund 2001).

Description of endemic fishes

The Tuira ecoregion contains fourteen endemic species, including Dasyloricaria capetensis, Dasyloricaria tuyrensis, Rineloricaria altipinnis, and Sturisomatichthys citurensis (Loricariidae); Amphilophus calobrensis and Vieja tuyrensis (Cichlidae); Brycon striatulus and Bryconamericus bayano (Characidae); Apteronotus rostratus (Apteronotidae); Characidium marshi (Crenuchidae); Neoheterandria cana (Poeciliidae); Piabucina festae (Lebiasinidae); and Pimelodus punctatus (Pimelodidae).

Justification for delineation

Fish provinces from Bussing (1976) were revised and subdivided based on application of a similarity index to sub-basin fish presence/absence data.

Level of taxonomic exploration

The level of taxonomic exploration is fair. More ichthyological work is required in the Tuira drainage basin as well as some of the southeastern drainages in Panama to fully characterize the fauna.