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Mediterranean Bioconstructions Along the Italian Coast 75

recently, Appolloni et al. (2018) published a comprehensive map of
coralligenous habitats in the Gulf of Naples. Most of the present studies have
been performed by means of remotely operated vehicles (ROVs) so as to
assess the status of deep assemblages associated to offshore shoals, and the
effects of fishery pressures (Ferrigno et al., 2017).
Deep surveys carried out along the Calabrian coast through ROV rev-
ealed a mixed assemblage of the black coral Antipathella subpinnata (Ellis &
Solander, 1786) and the sea fans P. clavata and E. cavolini from 50 to
100m depth in the Favazzina area. The extraordinary high density of this
assemblage is due to the northward current from the Strait of Messina
(Bo et al., 2009). In the Gulf of St. Eufemia, where currents slow down
and sedimentation is high, arborescent sea fans (e.g. Callogorgia verticillata
(Pallas, 1766), Paramuricea macrospina (Koch, 1882), P. clavata, Villogorgia
bebrycoides (Koch, 1887), Leptogorgia sarmentosa (Esper, 1789), C. rubrum
and Bebryce mollis Philippi, 1842) and antipatharians (e.g. A. subpinnata, Para-
ntipathes larix (Esper, 1788) and Antipathes dichotoma Pallas, 1766), as well as a
rich sponge assemblage settle on coralligenous shoals arising from a muddy
bottom. These habitats are small oases of hard substrata interspersed in a
muddy bottom (Bo et al., 2011, 2012a).
Coralligenous banks were recently described in the Sicily channel as out-
crops of dome-like pinnacles arising from a rocky plateau at about 100m
depth. Dense patches of the precious coral C. rubrum and of the sea fan
E. cavolini characterize the macrobenthic assemblage of these coralligenous
pillars. The lack of overlap between the two species suggests that they have
different ecological requirements. In this area the illegal fishing of C. rubrum
with trawling devices produces an intense impact on this peculiar assemblage
(Cattaneo-Vietti et al., 2017).
Finally, flourishing coralligenous assemblages dominated by filter-feeding
structuring species and a kelp canopy have been described also in offshore
locations such as the Vercelli and Palinuro seamounts in the Tyrrhenian
Sea between 60 and 120m depth (Bo et al., 2011; W€urtz and Rovere, 2015).

2.2.4 Cladocora caespitosa Formations/Reefs
Morri et al. (2000a) listed eight coral species as potential bio-
constructors in the Mediterranean Sea. Five of them, Dendrophyllia ramea
(Linnaeus, 1758), Dendrophyllia cornigera (Lamarck, 1816), Madrepora
oculata Linnaeus, 1758, Desmophyllum dianthus (Esper, 1794) and Lophelia
pertusa (Linnaeus, 1758), live in deep waters and will be treated later. Three
species, Madracis pharensis (Heller, 1868), Oculina patagonica de Angelis, 1908,