Biome: Tropical and Subtropical Moist Broadleaf Forests... Size: 46,100 square miles... Conservation Status: Relatively Stable/Intact..... Introduction: "The Kayah-Karen Montane Rain Forests [IM0119] ecoregion harbors globally outstanding levels of species richness. Among the ecoregions of Indochina, it ranks second for bird species richness and fourth for mammal species richness. The world?s smallest mammal, Kitti?s hog-nosed bat (Craseonycteris thonglongyai), equal in mass to a large bumblebee, resides in the limestone caves of this ecoregion. Because the ecoregion remains unexplored scientifically, especially the parts that lie in Myanmar, it probably will yield more biological surprises. Description Location and General Description This ecoregion includes the northern part of the Tenasserim Mountain Range, which forms the border between Thailand and Myanmar. Much of the region consists of hills of Paleozoic limestone that have been dissected by chemical weathering. The overhanging cliffs, sinkholes, and caverns characteristic of tropical karst landscapes are all present in this ecoregion. Large patches of limestone forest are associated with the tropical karst. The flora and fauna here is distinct and includes several endemic species. Because complex habitats are little explored, it is likely that they contain undescribed endemic species..."