New records of demosponges (Porifera) from the South Orkney Islands (Antarctica) with a checklist for the region Author Schejter, Laura Author Cristobo, Javier Author Ríos, Pilar text Zootaxa 2024 2024-01-23 5403 4 401 430 http://dx.doi.org/10.11646/zootaxa.5403.4.1 journal article 10.11646/zootaxa.5403.4.1 1175-5326 10562154 C2EAB19C-07CB-4013-9C93-D25259EA2673 Lissodendoryx (Ectyodoryx) anacantha ( Hentschel, 1914 ) ( Figure 4j–o ) Restricted synonymy: Ectyodoryx frondosa var. anacantha Hentschel, 1914 , Ectyodoryx anacantha Hentschel, 1914 . Material examined: 1 specimen collected at station 7 ( SOI ; 61°00'S , 46°44'W ; 609 m ; 3/3/2014 ; MACN-In 44386; IEO-CSIC Col.) . Description: Specimen erect, massive, beige in colour, with a conulose surface ( Figure 4j ). In the choanosomal skeleton, the principal acanthostyles are disposed in multispicular axes. Spicules are acanthostyles I, spined only at their tips, of 470–660 µm by 30 µm; acanthostyles II completely spined 210–320 µm by 10–15 µm; strongyles also spined at their tips of 230–300 µm by 7.5 µm, arcuate isochelae, 25 µm with curved alae and two categories of sigmas of 50–55 µm and 20–25 µm ( Figure 4k–o ). Remarks: This species is distributed in the Antarctic domain. It was previously recorded by Hentschel (1914) at the East Antarctic Wilkes Land ( type locality) and at Kermadec Island, at Palmer Archipelago (Antarctic Peninsula) by Burton (1932) , at the South Shetland Is. and East Antarctic Wilkes Land by Koltun (1964) and Ríos (2006) . This is the first report for the SOI.