Biodiversity & Conservation

Caves and overhangs (deep)


Caves and overhangs (deep)
Distribution map

CR.FCR.Cv recorded (dark blue bullet) and expected (light blue bullet) distribution in Britain and Ireland (see below)

  • EC_Habitats

For a list of 2004 characterising species please see the JNCC website.

Species indicative of sensitivity

To assess the sensitivity of the biotope, the sensitivity of component species is reviewed. Those species that are considered to be particularly indicative of the sensitivity of the biotope, and for which research has been undertaken in detail are shown below (see selection criteria). The biology of other component species of the biotope is also taken into account wherever information is known to the researcher.

Species found especially in this biotope

  • Leptopsammia pruvoti

Rare of scarce species associated with this biotope

Community Importance Species name Common Name
Important characterizing Leptopsammia pruvoti Sunset cup coral
Important characterizing Caryophyllia smithii Devonshire cup coral
Important characterizing Alcyonium glomeratum Red sea fingers


The biotope is particularly characterized by sponges and anthozoans including several cup coral species. In the absence of full MarLIN research for all but Leptopsammia pruvoti, research has been undertaken on relevant aspects of the biology of particular species and a knowledge of the results of monitoring the biotope in south-west England (Fowler & Pilley, 1992 and researchers own observations). Two of the species of coral have different life cycles with Caryophyllia smithii producing a planktotrophic larva and likely to colonise readily whilst Leptopsammia pruvotihas a lecithotrophic probably short-lived larva and most likely also represents Hoplangia durotrix in its larval biology. The reproductive biology of Alcyonium hibernicum has been researched (Hartnoll, 1977 as Alcyonium coralloides) whilst Alcyonium glomeratum is known to colonize wrecks readily (researchers own observations) suggesting good recolonization potential.

Additional information

Whilst the structural and functional aspects of the biotope are similar across its range, species composition varies. The species composition of the biotope includes a small number of nationally rare or scarce species.

This review can be cited as follows:

Hiscock, K. 2000. Caves and overhangs (deep). Marine Life Information Network: Biology and Sensitivity Key Information Sub-programme [on-line]. Plymouth: Marine Biological Association of the United Kingdom. [cited 28/11/2015]. Available from: <>