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In corals where complex life history processes decoupling age from size (e.g., fragmentation, fusion, partial colony mortality) are rare or clearly detectable, individual age may be determined from size, and age-based growth and population dynamic models may be applied. One example is the solitary Mediterranean coral Leptopsammia pruvoti Lacaze-Duthiers 1897, whose population size and structure, and growth rates were determined at Calafuria (43°28'N and 10°20'E), Ligurian Sea, from December 2007 to June 2009. Growth rate decreased with increasing size. The growth curve derived from field measurements confirmed the one obtained by growth band analysis. The frequency of individuals decreased exponentially with age, indicating a steady state population. Turnover time was 2.3 years. Maximum life span was 13 years. Most reproductive output was from intermediate age classes (6 years), while older individuals (>7 years), although having higher fecundity, were rare and accounted for a minority of population reproductive output. In comparison with other solitary dendrophylliids, L. pruvoti life strategy was characterized by a reproduction with r-strategy correlates (high fecundity, short embryo incubation, small planula size, fast achievement of sexual maturity), and a rate of demographic renewal occurring halfway along the r-K continuum (intermediate turnover time and maximum longevity)., Author(s): Stefano Goffredo [sup.1] , Erik Caroselli [sup.1] , Guido Mattioli [sup.2] , Francesco Zaccanti [sup.1] Author Affiliations: (1) grid.6292.f, 0000000417571758, Marine Science Group, Department of Evolutionary and Experimental Biology, [...]

The correlation between solar radiation and sea surface temperature (SST) and growth was assessed along a latitudinal gradient. Extension rate and skeletal density were both correlated with calcification rate, indicating that calcium carbonate deposition was allocated evenly between skeletal density and linear extension. Unlike most studies on other tropical and temperate corals, in which calcification was positively correlated with solar radiation and SST, in the present study calcification was not correlated with solar radiation, whereas it was negatively correlated with SST. We hypothesize that photosynthesis of the symbiotic algae of Balanophyllia europaea is inhibited at high temperatures, consequently causing an inhibition of calcification. The regressions between calcification and SST predicted that the calcification of B. europaea would be depressed at 20.5-21.0[degrees]C mean annual SST. The scenarios of the Intergovernmental Panel on Climate Change conclude that by 2100, SST will exceed this physiological threshold for most of the populations considered in this study. This study comprises the first field investigation of the relationships between environmental parameters and calcification of a Mediterranean coral and highlights the risks of losing Mediterranean marine biodiversity over the course of future decades.