Boundaries

This ecreogion includes the Tenasserim River from the Lenya basin northwards and the Salween basin to around the Myanmar-Chinese border. It also includes several subterranean systems in Thailand, inhabited by endemic cave fishes and crustaceans.

Description of endemic fishes

The ecoregion contains 45 recorded endemic species.

Justification for delineation

For Southeast Asia, delineations were determined using a bottom-up approach that employed both published and unpublished field data and expert assessment (Abell et al. 2008). The data, though scanty, suggests some affinities between the Tenasserim and Salween, but it does not indicate whether this is a single ecoregion. It is similarly difficult to delineate the boundary between middle and upper Salween [ecoregion 721] (M. Kottelat pers. comm. 2006).

Level of taxonomic exploration

The data is extremely limited for the Salween basin (outside Thailand) and close to non-existing for the Tenasserim basin.