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) ramilobosa ( Topsent, 1916 ) ( Fig 4d–i ) Restricted synonymy: Dendoryx ramilobosa Topsent, 1916 , Ectyodoryx ramilobosa ( Topsent, 1916 ) . Material examined: 6 specimens collected in stations 1 ( SOI ; 60°28'S , 46°29'W ; 139 m ; 19/2/2014 ; MACN-In 44382; IEO-CSIC Col.), 4 ( SOI ; 60°55'S , 44°04'W ; 256 m ; 2/3/2014 ; MACN-In 44383; IEO-CSIC Col.), 6 ( SOI ; 61°25'S , 44°37'W ; 290 m ; 3/3/2014 ; MACN-In 44384), 7 ( SOI ; 61°00'S , 46°44'W ; 609 m ; 3/3/2014 ; IEO-CSIC Col.) and 10 ( SOI ; 60°59'S , 46°43'W ; 307 m ; 5/3/2014 ; MACN-In 44385) . Description: Body elongate, formed by a number of anastomosed branches; surface covered by rounded conules ( Figure 4d ). Some specimens were attached to rocks. Spicules are two categories of styles (that may have spinules at the tip) of 470–700 μm by 20–40 μm and 200–370 μm by 17.5–20 μm; strongyles with spiny tips of 240–310 μm by 5–7.5 μm; arcuate isochelae of 15–25 μm and S and C contorted sigmas in two categories, 50–65 μm and 15–20 μm ( Figure 4e–i ). Remarks: This is a common, well-described Antarctic species already recorded by Koltun (1964) , Göcke & Janussen (2013) , Ríos (2006) and Fernández et al. (2021) , among others. However, this is the first record for the SOI.