Survey of Subterranean Life

A wide variety of organisms are found in subterranean habitats and they have varying degrees of dependence and permanence in these habitats. Some species, stygobionts and troglobionts, have an obligate dependence on subterranean habitats, and are found nowhere else. Other species have an obligate dependence on caves and other subterranean habitats, such as bats and aquatic insects, but only spend part of their life cycle in caves (stygoxenes and trogloxenes). Others can spend their life cycle in or out of caves (stygophiles and troglophiles). There are 21 invertebrate orders that have over 50 stygobiotic and troglobiotic species. Among vertebrates, salamanders and especially fishes are also well represented in caves and deep aquifers. Although the information obtained is very informative, very few subterranean species have been maintained successfully in the laboratory. There are a few specialized collecting techniques that are very useful, especially in non-cave subterranean habitats.