Antipathella subpinnata as a model species: life history and autoecology

Communication for the 79th Congress of the Italian Zoological Union, Lecce, 2018

The black coral fauna of the Mediterranean Sea includes seven species belonging to five different families distributed throughout the basin from 60 to 2000 m depth. For long time considered extremely rare species, in the last 10 years, remotely operated vehicle (ROV) explorations completely overturned this paradigm such that, now, at least 4 of these species are considered common or dominant components of the deep circalittoral and bathyal cold-water corals (CWC) assemblages. A large effort has been dedicated to map the distribution of populations, however very little information exists on the life history and ecological role of these paramount species. 

In particular, Antipathella subpinnata, a large arborescent species, is known to thrive from 60 to 600 m depth on exposed hardgrounds commonly forming dense aggregations. Over 70 populations have been currently mapped in the Mediterranean basin; therefore, this species may well represent a model for the entire order. A 360° approach (coupled to literature search) has been carried out to investigate, in the field and in controlled systems, numerous traits of the life history of this species and to elucidate its ecology. In particular: i) phylogenetic position, ii) morphological characteristics, iii) phenotypic plasticity, iv) geographic and bathymetric distribution, v) size frequency distribution, vi) habitat preferences, vii) associated fauna, viii) associated microbiome, ix), sexual reproductive cycle, x) asexual reproduction through fragmentation, xi) genetic structuring and connectivity among populations, xii) growth rates, xiii) isotopic diet, xiv) skeletal degradation, xv) 3D modelling and biomass, xvi) response to anthropic impact. 

Although various aspects have not been investigated yet (e.g. age, skeletal architecture, larval ecology), such extensive dataset is crucial when identifying the vulnerability traits of a species and of the ecosystem it sustains.