Karst
Ancient limestones have eroded into extensive karst formations in some areas, creating a network of sinkholes, underground streams, caves and unusual communities on limestone. During the Pleistocene glaciations, the Appalachians acted as a mesic and thermal refuge for a number of species and communities. In a similar manner, after the retreat of the glaciers, cold-adapted communities, such as cranberry bogs, remained in refugia in cooler portions of the Appalachians, well south of their usual range. The prevalent limestone and karst formations in this ecoregion are associated with a cave fauna of salamanders, fish, and invertebrates. The diversity and distribution of these species are not well known, but they likely rival cave faunas around the world in richness and endemism. Cave habitats in the Appalachian LCC support several federally listed species including the Madison cave isopod, Townsend’s big-eared bat and Indiana bat.