New species of black corals (Cnidaria: Anthozoa: Antipatharia) from deep- sea seamounts and ridges in the North Pacific Author Opresko, Dennis M. 0000-0001-9946-1533 Department of Invertebrate Zoology, U. S. National Museum of Natural History, Smithsonian Institution, Washington, DC 20560. Conservation International, Center for Oceans, Arlington, VA. & dmopresko @ hotmail. com; https: // orcid. org / 0000 - 0001 - 9946 - 1533 dmopresko@hotmail.com Author Wagner, Daniel 0000-0002-0456-4343 dwagner @ conservation. org; https: // orcid. org / 0000 - 0002 - 0456 - 4343 dwagner@conservation.org text Zootaxa 2020 2020-10-29 4868 4 543 559 journal article 8935 10.11646/zootaxa.4868.4.5 89de8b03-b1c0-4580-b988-561f7e381264 1175-5326 4418112 435A24DF-6999-48AF-A307-DAFCC5169D37 Alternatipathes Molodtsova and Opresko, 2017 Diagnosis. Corallum attached to substrate; monopodial, unbranched or with a few basal branches, and pinnulate. When present, pinnate branches of first order develop from lowermost pinnules of stem. Pinnules simple, arranged alternately in two lateral rows. Length of pinnules on stem and branches usually decreasing in a distal direction forming a triangularly shaped outline. Striatum absent. Spines conical, smooth, simple (or rarely forked), with acute to slightly rounded apex and flared base. Spines often larger on polypar side of pinnule. Polyps 2–7 mm in transverse diameter. Type species. Umbellapathes bipinnata Opresko, 2005 . Remarks. Three species are currently assigned to this genus; A . bipinnata ( Opresko, 2005 ) , A . alternata ( Brook, 1889 ) , and the new species described below.