MA1-55 - Biocénose des grottes et surplombs du médiolittoral en Méditerranée (EUNIS 2022)

MA1-55 - Biocénose des grottes et surplombs du médiolittoral en Méditerranée

Biocenosis of Mediterranean mediolittoral caves and overhangs

MA1-54 - Biocénose de la roche du médiolittoral inférieur en Méditerranée

Classification des habitats EUNIS 2022

Descriptif de l'habitat

Mediolittoral caves correspond to crevices or the entrances of caves that are partially out of the water. These are usually located in karstic or volcanic systems.
These formations can be almost totally covered by the sea, and as one penetrates further into the submerged part two other habitats can be made out – the semi-dark caves and the caves in total darkness. In the exposed cavity formations, a terrestrial fauna is found based on acari, pseudo-scorpions and Chilopoda. The supralittoral and – especially – mediolittoral parts are covered with crust-forming algae.
The crevices or the entrances of the caves present variation gradients of the ambient factors that are essential for the distribution of species: reduction in hydrodynamics, and in light. The bottom of these cavities presents an area of very high humidity that encourages organisms that usually live more deeply to live there, and this results in the zonation getting mixed up.
Given the reduced hydrodynamics, there is in this habitat an accumulation of floating detritus and objects.
The variability is linked to both the size of crevice or cave, and the position of the openings in relation to the dominant hydrodynamics. The cave’s geomorphology and the possibility of a flow of fresh water also have a big influence on the quality itself of the habitat and its development over time.

Bibliography

European Topic Centre on Biological Diversity 2022. EUNIS marine habitat classification 2022 including crosswalks. Table Excel. (Source)