A new calcaxonian genus and family for Trichogorgia utinomii Cordeiro, 2019 (Octocorallia, Alcyonacea): new records of a scleriteless gorgonian species from Antarctica

A new genus of scleriteless gorgonian, Huziogorgia gen. nov., is proposed based on the morphological and molecular study of a set of colonies identified as the recently described species Trichogorgia utinomii Cordeiro, 2019 . Huziogorgia utinomii comb. nov. has planar colonies, lyrate to dichotomous, with long and flexible terminal branches. The polyps are no retractile, always extended, slightly trumpet-shaped, biserially placed, but not strictly. The axis is circular in cross section, showing concentric non-undulated layers. The materials were collected during three Antarctic cruises to the Antarctic Peninsula and South Shetland islands onboard the RV Polarstern (ANT XIX/3, ANT XXIII/8, and ANT XXIX/3). A molecular comparison based on mitochondrial genes ( mtMutS and mtMutS + Igr1 + COI ) relates the new genus to the family Ifalukellidae Bayer, 1955 ( Ifalukella Bayer, 1955 , Trichogorgia (Hickson, 1904 ), Plumigorgia Nutting, 1910) and some genera of uncertain relationships, but currently related to the family Chrysogorgiidae Verrill, 1883 ( Pleurogorgia Versluys, 1902 and Stephanogorgia Bayer & Muzik, 1976 ) . Genetic distances between this species and the closest genera and families also suggest the separate placement of Huziogorgia gen. nov. in a new family, Huziogorgiidae fam. nov.