First Ecological Characterization of Whip Black Coral Assemblages (Hexacorallia: Antipatharia) in the Easter Island Ecoregion, Southeastern Pacific

One of the main priorities marine scientific research is to provide practical information and guidance for biodiversity conservation management. In this context, identification key fragile habitat-forming species particularly important. Despite their ecological importance, whip corals in order Antipatharia remain poorly studied around world, especially South Pacific. During recent expeditions explore mesophotic deep benthic habitats Rapa Nui (Easter Island), dense assemblages black were observed situ . We here report first detailed description distribution abundance these coral associated fauna habitat. These descriptions based on analysis video surveys collected 67 remotely operated vehicle dives conducted 2014 through 2019 at three sites (Pukao seamount, Apolo peak, Island shelf slope) within Easter Ecoregion depths between 50 330 m. At least four morphotypes (yellow, red, white/orange, Pukao) unbranched detected. Each morphotype had polyps arranged a single row only one side corallum, diagnostic morphological character currently assigned antipatharian genus Stichopathes Samples yellow red using molecular techniques. analyses indicate that not monophyletic requires further revisions, conclusion consistent with previous studies. Extensive fields corals, primarily morphotype, present 28 from 60 245 m rocky substrates, coarse sand, or rhodoliths. Densities per frame up 58.2 ± 5.2 colonies –2 (average: 13.2 0.8), which represent some highest reported densities date. Numerous faunal groups, including ophiuroids, echinoids, fishes, assemblages. Our observations should be considered future management efforts Nui, where multi-use protected area was established 2018, as well adjacent international waters unprotected but likely harbor similar