Troglophile

Troglofauna are small cave-dwelling animals that have adapted to their dark surroundings. Troglofauna and stygofauna are the two types of subterranean fauna (based on life-history). Both are associated with subterranean environments – troglofauna are associated with caves and spaces above the water table and stygofauna with water. Troglofaunal species include spiders, insects, myriapods and others. Some troglofauna live permanently underground and cannot survive outside the cave environment. Troglofauna adaptations and characteristics include a heightened sense of hearing, touch and smell. Loss of under-used senses is apparent in the lack of pigmentation as well as eyesight in most troglofauna. Troglofauna insects may exhibit a lack of wings and longer appendages.

Troglofauna are divided into three categories, troglophiles, trogloxenes and troglobites, based on their life-history.

Troglofauna usually live in moderate cave regions. The overall climates of these caves do not significantly change throughout the year. Humidity in such caves is generally high ranging from 95 to 100 percent; evaporation rates are low.

The cave ecosystem in which troglofauna reside can be divided into four zones: entrance, twilight, transition and deep cave. The entrance zone is where the surface and underground environments meet. Light becomes scarcer in the twilight zone. The transition zone is almost completely dark; however some outside environmental effects can still be felt. Finally the deep cave zone is completely dark, relatively stable, and exhibits no evaporation. Troglobites are usually found in the deep cave zone.

Troglofauna have adapted to the limited food supply and are extremely energy efficient. Food is found from "twigs, leaves, bacteria and epigean animals (including zooplankton)." Food is also found from trogloxene carcasses, egg deposits, and faeces such as bat guano. Troglofaunal beetles are predators and may feed on other troglofaunal animals rather than bacteria, twigs and guano.

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