A troglobite (or, formally, troglobiont) is an animal species, or population of a species, strictly bound to underground habitats, such as caves. These are separate from species that mainly live in above-ground habitats but are also able to live underground (eutroglophiles), and species that are only cave visitors (subtroglophiles and trogloxenes). Land-dwelling troglobites may be referred to as troglofauna, while aquatic species may be called stygofauna, although for these animals the term stygobite is preferable. Troglobites typically have evolutionary adaptations to cave life. Examples of such adaptations include slow metabolism, reduced energy consumption, better food usage efficiency, decrease or loss of eyesight (anophthalmia), and depigmentation (absence of pigment in the integument). Conversely, as opposed to lost or reduced functions, many species have evolved elongated antenna and locomotory appendages, in order to better move around and respond to environmental stimuli. These structures are also full of chemical, tactile, and humidity receptors. Troglobites commonly do not survive well outside caves and therefore cannot travel between separate cave systems. As a result, many troglobiotic species are endemic to a single cave or system of caves. Not all cave dwelling species are considered to be troglobites. An animal found in an underground environment may be a troglophile (a species living both in subterranean and in epigean habitats, e.g. bats and cave swallows) or a trogloxene (a species only occurring sporadically in a hypogean habitat and unable to establish a subterranean population).

Flatworms

Mollusca

Bivalvia

Gastropoda

Velvet worms

Arthropoda

Arachnida

Myriapoda

Crustacea

• Cambarus aculabrum – Benton County cave crayfish • Cambarus cryptodytes – Dougherty Plain cave crayfish • Cambarus hamulatus – Prickly cave crayfish • Cambarus hubrichti – Salem cave crayfish • Cambarus jonesi – Alabama cave crayfish • Cambarus laconensis – Lacon Exit cave crayfish • Cambarus nerterius – Greenbrier cave crayfish • Cambarus pecki – phantom cave crayfish • Cambarus setosus – Bristly cave crayfish • Cambarus speleocoopi – Sweet Home Alabama cave crayfish • Cambarus subterraneus – Delaware County cave crayfish • Cambarus tartarus – Oklahoma Cave Crayfish • Cambarus veitchorum – White Spring cave crayfish • Cambarus zophonastes – Hell Creek cave crayfish • Faxonius stygocaneyi – Caney Mountain cave crayfish • Orconectes australis – Southern cave crayfish • Orconectes barri – Cumberland Plateau cave crayfish • Orconectes incomptus – Tennessee cave crayfish • Orconectes inermis – Northern cave crayfish • * Orconectes inermis inermis – ghost crayfish • * Orconectes inermis testii – unarmed crayfish • Orconectes packardi – Appalachian cave crayfish • Orconectes pellucidus – Mammoth Cave crayfish • Orconectes sheltae – Shelta cave crayfish • Procambarus acherontis – Orlando cave crayfish • Procambarus attiguus – Silver Glen Springs cave crayfish • Procambarus cavernicola – Gabriel cave crayfish • Procambarus clarkii – Louisiana crayfish (in Portugal and Italy) • Procambarus delicatus – big-cheeked cave crayfish • Procambarus erythrops – Santa Fe cave crayfish • Procambarus franzi – Orange Lake cave crayfish • Procambarus horsti – Big Blue Spring cave crayfish • Procambarus leitheuseri – Coastal Lowland cave crayfish • Procambarus lucifugus – Florida light-fleeing cave crayfish • * Procambarus lucifugus lucifugus – Withlocoochee light-fleeing cave crayfish • * Procambarus lucifugus alachua – Alachua light-fleeing cave crayfish • Procambarus milleri – Miami cave crayfish • Procambarus morrisi – Putnam County cave crayfish • Procambarus niveus – Cuban cave crayfish • Procambarus orcinus – Woodville Karst cave crayfish • Troglocambarus maclanei – North Florida Spider Cave Crayfish • Troglocambarus sp. 1 – Orlando Spider Cave Crayfish

Insecta

Fish

Amphibians

Mammals

No known mammals live exclusively in caves. Most bats sleep in caves during the day and hunt at night, but they are considered troglophiles or trogloxenes. However some fossorials which spend their whole lives underground might be considered subterranean fauna, although they are not true troglofauna as they do not live in caves.

Echinodermata

Porifera

Annelida

In popular culture

There is a zombie named the Troglobite in Plants vs. Zombies 2.