Mekong Delta




J. Hales




Pending review.

Major Habitat Type

large river deltas

Drainages flowing into

South China Sea

Main rivers to other water bodies

Mekong River, Tonle Sap River, Tonle Sap Lake, Tri An Lake, Dong Nai River



This ecoregion includes the lower Mekong and its tributaries entering it downriver of the confluence with the Prek Chhlong River. It includes Tonle Sap, the Mekong Delta and its peat swamp forests. The ecoregion extends east to the Dong Nai basin.

Terrestrial habitats

This ecoregion includes Southeastern Indochina dry evergreen forests, Central Indochina dry forests, Cardamom Mountains rain forests, Tonle Sap-Mekong peat swamp forests, Tonle Sap freshwater swamp forests, and Indochina mangroves (Wikramanayake et al. 2002).

Description of endemic fishes

This ecoregion has only a handful of recorded endemics, including Akysis similis, Hemibagrus spilopterus, Kryptopterus paraschilbeides, and Tuberoschistura cambodgiensis.

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For Southeast Asia, delineations were determined using a bottom-up approach that employed both published and unpublished field data and expert assessment (Abell et al. 2008; Rainboth 1996). This ecoregion is distinguished, among other features, by the Great Lake (Tonle Sap), Mekong Delta, and possibly peat swamp forests in the Mekong Delta (M. Kottelat pers. comm. 2006).


  • Abell, Robin,M.L. Thieme,C. Revenga,M. Bryer,M. Kottelat,N. Bogutskaya,B. Coad,N. Mandrak,S.C. Balderas,W. Bussing,M.L.J. Stiassny,P. Skelton,G.R. Allen,P. Unmack,A. Naseka,R. Ng,N. Sindorf,J. Robertson,E. Armijo,J.V. Higgins,T.J. Heibel,E. Wikramanayake, (2008). "Freshwater Ecoregions of the World: A New Map of Biogeographic Units for Freshwater Biodiversity Conservation" BioScience 58 (5) pp. 403-414.
  • Kottelat, M. (1989). "Zoogeography of the fishes from Indochinese inland waters with an annotated check-list" Bulletin Zoologisch Museum Universiteit van Amsterdam 12 (1) pp. 1-54.
  • Wikramanayake, Eric,Dinerstein, Eric,Loucks, C.,Olson, D.M.,Morrison, J.,Lamoreux, J. L.,McKnight, M.;Hedao, P. (2002). "Terrestrial ecoregions of the Indo-Pacific: A conservation assessment" Washington, DC: Island Press.
  • Rainboth, W. J. (1996). "Fishes of the Cambodian Mekong" Rome: FAO.