Note on new records of living Scleractinia and Gorgonaria between 1700 and 2200 m depth in the western Mediterranean Sea

While living corals were mainly reported to live at depths shallower than 1200 m, their pleistocene fossils in the form of Pleistocene fossils are found at depths of ca. 2000 m in the Mediterranean Sea. This was found after in-situ observations during dives of the Nautile submarine in the Canyon of Stoechade (France). During these dives, living specimens of sea fans ( Acanthogorgia hirsuta , Isidella elongata, Placogorgia massiliensis ) and hard corals ( Javania cailleti ) were observed and collected at depths of between 1700 and 2200 m. In an attempt to explain this unexpected find, it has been speculated that general conditions in northern canyons may be more favorable to the deep occurrence of these organisms than the central and southern areas of the Mediterranean, where no living Scleractinia or Gorgonaria have been observed at similar depths.