Troglofauna are obligate air-breathing, underground invertebrate taxa. They cannot live above ground so are completely restricted to the subterranean environment.

Like stygofauna, troglofauna have evolved a range of morphological and physiological adaptations suited to subterranean habitats such as:
  • Lack of eyes
  • Lack of pigmentation
  • Elongate (filiform) body shape to move through tight spaces
  • Highly sensitive and long antennae and sensory mechanisms
Troglofauna have reduced metabolic activity to cope with relatively limited food supplies and oxygen levels in subterranean environments.

Western Australian troglofauna are considered to be possibly rainforest relicts. Breeding appears to occur in the Pilbara region during the wet season (November March), when cyclonic rains transport food and oxygen down into their subterranean habitats.

Similar timing responses probably occur in the Kimberley. Elsewhere in Western Australia, such as the Goldfields or Murchison regions, where rainfall is more erratic, breeding and population expansion are likely to occur immediately after large rainfall events.

These biological responses have implications for survey design and timing.

Troglofauna are typically divided into three categories of specialization to subterranean life1, 2, 3:
  • Troglobites: entirely restricted to subterranean habitats and die on exposure to the surface
  • Troglophiles: facultatively use subterranean habitats but do not rely on them for survival
  • Trogloxenes: use underground systems for specific purposes but do not rely on them for survival.
Troglofauna of conservation value include troglobites and troglophiles. Some troglophiles appear to be widespread species, while others, like diplurans and cryptopids, are often short-range endemics.

The diversity of troglofauna and their identification challenges demonstrate the importance of taxonomic expertise and appropriate survey design.

REFERENCES
  1. Barr 1968 Barr, T. C. 1968. Cave ecology and the evolution of troglobites. In: Dobzhansky, T., Hecht, M. K. & Steere, W. C. (eds) Evolutionary biology. North-Holland, Amsterdam, pp. 35102.
  2. Howarth 1983 Howarth, F. G. 1983. Ecology of cave arthropods. Annual Review of Entomology 28: 365389.
  3. Humphreys 2000 Humphreys, W. F. 2000. Background and glossary. In: Wilkens, H., Culver, D. C. & Humphreys, W. F. (eds) Ecosystems of the World Vol. 30 - Subterranean ecosystems. Elsevier, Amsterdam, pp. 314.