Thermal stress response of Antipathella wollastoni (Gray, 1857) from the Canary Islands archipelago

Abstract

The present study aims at assessing the thermal tolerance of the black coral Antipathella wollastoni (Gray, 1857), which forms extensive forests in multiple Macaronesian islands. Fragments of A. wollastoni were exposed for 15 d to temperature conditions ranging from 19 to 26.5 °C, and multiple endpoints were investigated. No mortality was observed, and total antioxidant capacity remained unaffected by temperature increase. Respiration rates described a Gaussian relationship and tissue necrosis a linear increase with temperature. Increased temperature triggered the formation of bailout propagules, a process that may be used by the species as an escape strategy under unfavourable environmental conditions. Propagules of A. wollastoni were described for the first time. Altogether, A. wollastoni was suggested to have low vulnerability to increased temperatures, owing to its wide thermal window of performance (9.7 °C) and thermal safety margin (1.2 °C), similar to its congeneric Mediterranean Antipathella subpinnata.