A Mediterranean “roche du large” ecosystem, represented by four rocky shoals, located a few miles apart on a muddy bottom at 70–130 m depth in the gulf of St. Eufemia (Calabria, South Tyrrhenian Sea), was studied by means of Remotely Operated Vehicle (ROV) photo imaging. The shoals host highly diversified coral communities, mainly composed of arborescent colonies of gorgonians (Callogorgia verticillata, Paramuricea clavata, Paramuricea macrospina, Bebryce mollis, Villogorgia bebrycoides, Corallium rubrum, and Leptogorgia sarmentosa), and antipatharians (Antipathella subpinnata, Antipathes dichotoma and Parantipathes larix). The coral colonies reach high densities (up to ca. 17 colonies m−2) and large sizes, such as the over 1.5 m wide antipatharian colonies. We hypothesized that the abundance and composition of the coral assemblages differed significantly among the rocky shoals and with respect to the surrounding soft bottoms. Various environmental variables were tested as possible explanatory factors of the observed differences. Moreover, due to their off-coast localization, we report here that these unique ecosystems are potentially subjected to a strong pressure from the local fishing activities, which were tentatively characterized. The recorded coral β-diversity among the shoals supports the hypothesis that these habitats behave like small oases of hard substrata interspersed in a muddy bottom. Because of their intrinsic beauty and rarity and their biological and ecological value, we stress the need of specific actions aimed at the urgent protection of these oases of biodiversity.
Errina aspera is the only species belonging to the family Stylasteridae known from the Mediterranean Sea. The distribution of this species includes the Messina Strait, the Gibraltar Strait and the Atlantic coast of Morocco. In spite of the taxonomic and biogeographical importance of this species, no studies were conducted on its population structure in the Messina Strait. Here we report a study carried out with the aid of a ROV on a horizontal transect 350 m long at a depth comprised between 83 and 105 m where an extremely dense population of this stylasterid (101.4 ± 13.3 m−2) was recorded. The main components of the benthic community other than E. aspera are the coralline alga Lithothamnion philippii and the white zoanthid Epizoanthus sp. The colonies of E. aspera have a height ranging between 1.2 and 18.8 cm (4.1 ± 0.1 cm on average); they generally show a bi-dimensional, fan shaped morphology, but three-dimensional, brush-like specimens are also observed. The size–frequency distribution of the colony height is unimodal with a mode in the classes of 3–5 cm and a long tail of rare large colonies suggesting that the current may act as a limiting factor for the colony growth. The association with the gastropod ovulid Pedicularia sicula is confirmed.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.