Description of Caves and ducts in total darkness (including caves without light or water movement at upper levels)
This habitat occurs in very large submerged cavities especially present in drowned karstic networks, isolated little cavities and microcavities in heaps of stones and within certain concretions. The caves in total darkness are enclaves of the aphotic area in the littoral area. These habitats present extremely original environmental conditions, close to those found on the continental slope. The two most important ecological factors are the absence of light, which rules out photosynthetic organisms, and the confined space.