Diversity and distribution of noctilucoid dinoflagellates (Noctilucales, Dinophyceae) in the open Mediterranean Sea

International audienceThe noctilucoid dinoflagellates have been investigated in the open waters of the Mediterranean Sea. Kofoidinium spp., Spatulodinium spp. and Scaphodinium mirabile were found in nearly all the stations. The genera Craspedotella, Leptodiscus, Petalodinium and Pomatodinium were recorded for the first time in the eastern Mediterranean basin. An undescribed small species of Kofoidinium (40-60 μm in diameter) with a pointed extension represented about 1/3 of the genus records. The monotypic character of the genus Spatulodinium needs to be reconsidered because numerous specimens differed from the type species. One of these undescribed species showed a distinctive hyposome and an extremely long tentacle (up to 1600 μm long). A leptodiscacean that showed an arrowhead-shaped contour is found for the first time in the Mediterranean Sea. There is a considerable diversity of noctilucaceans yet to be describe