Overlooked biodiversity from museum collections: four new species and one new genus of Ophiuroidea (Echinodermata) from Antarctica and adjacent regions with notes on multi-armed ophiuroids

Four newly described species, Astrochlamys timoharai sp. nov. (Gorgonocephalidae Ljungman, 1867), Ophiosteira lissopatella sp. nov. (Ophiopyrgidae Perrier, 1893), Ophiophyllum umbonatum sp. nov. (Ophiopyrgidae), and Soliophis bakeri sp. nov. (Ophioscolecidae Lutken, 1869) with a description of Soliophis gen. nov., are reported from the Ross Sea and adjacent regions. New occurrence of Euvondrea floretta Fell, 1961a is also reported. These newly described taxa display unusual morphology with two species showing 10 or more arms. Although no evidence of brooding was present, two of the described species belong to genera with other Antarctic species that show brooding behavior. Collections from these areas remain important for new discoveries relevant to Antarctic biodiversity.