New sea cucumber species from the seamounts on the Southwest Indian Ocean Ridge (Echinodermata: Holothuroidea: Aspidochirotida, Elasipodida, Dendrochirotida) Author O’Loughlin, P. Mark Author Mackenzie, Melanie Author VandenSpiegel, Didier text Memoirs of Museum Victoria 2013 2013-12-10 70 37 50 https://museumsvictoria.com.au/collections-research/journals/memoirs-of-museum-victoria/volume-70-2013/pages-37-50/ journal article 10.24199/j.mmv.2013.70.04 1447-2554 12208349 DECF956F-C474-4C8D-82AF-48FD0EC0BB4A Pannychia taylorae O’Loughlin sp. nov. Zoobank LSID. http://zoobank.org/ urn:lsid:zoobank.org:act: 77705FFB-3331-44AC-9266-BDD53F760E49 Figures 1 , 5 , 6 , 7 , table 1 Material examined . Holotype . Southwest Indian Ocean Ridge, Coral Seamount, 41.38ºS 42.85ºE , 1286 m , JC066, specimen no. JC066– 204, ROV, 13 Nov 2011 , NHMUK 2013.5. Description. Body wall thick, soft; body with low elevation, rounded anteriorly and posteriorly, slight brim marginally, body 180 mm long, up to 45 mm wide; numerous dorsal and lateral thin papillae evident in photo of live animal, few remaining on preserved holotype , up to about 15 mm long; mouth subventral, anus dorsoposterior; damaged orally, 16 of 20 tentacles remaining; single series of 19 tube feet on each lateroventral ambulacrum, median ventral ambulacrum with 23 smaller tube feet in paired series posteriorly, more scattered anteriorly. Ossicles in dorsal and ventral body wall and dorsal papillae abundant wheels and small concave oval to round plates; wheels up to 328 µm diameter, 9–15 outer spokes, rounded triangular teeth between the bases of the spokes, central wheel hub with 5–7 spokes, predominantly 6 never 4, hub covered by a membrane; small plates about 56 µm long, up to about 70 µm long, irregularly oval to round, slightly lobed margin, slightly concave, about 15 perforations, typically 11 marginally with 4 centrally, sometimes 2 larger centrally. Tentacle ossicles rarely branched, curved rods with thick spines on outer surface, rods up to 350 µm long. Colour. Live: body pale blue, tentacle and tube foot ends pale brown. Preserved: body off-white, tentacle and tube feet ends pale brown. Distribution. Southwest Indian Ocean, Coral Seamount, 1286 m . Etymology. Named for Michelle Taylor (Department of Zoology, University of Oxford) in appreciation of Michelle’s tireless and efficient work in organizing the biological science team and processing the collections for voyage JC066. Figure 5. Photos of live holotype specimen of Pannychia taylorae O’Loughlin sp. nov. (NHMUK 2013.5). a, photo of live holotype specimen ( in situ on Coral Seamount; taken by ROV during cruise JC066; copyright AD Rogers University of Oxford/NERC); b, ventral view of live holotype (with two commensal polynoid specimens) (photo taken by David Shale and used with permission). Figure 6. Photos of holotype of Pannychia taylorae O’Loughlin sp. nov. (preserved, 180 mm long, NHMUK 2013.5). Ventral view of holotype with oral end below and midventral tube feet more numerous posteriorly. Insert with ventral view of damaged oral region showing non-retractile tentacles. Figure 7. SEM images of ossicles from holotype of Pannychia taylorae O’Loughlin sp. nov. (NHMUK 2013.5). a, tentacle rods with outer surface spines (scale bar 50 µm; small plate ossicle probable contaminant from body wall); b, wheels from dorsal body wall (scale bars 100 µm); c, wheels and small plates from dorsal papilla (scale bars 50 µm); d, small concave plates from ventral body wall (scale bars 10 µm). Remarks. The single type specimen of P. taylorae O’Loughlin sp. nov. is closest in its morphological characters to the Antarctic Admiralty Seamount specimens that we have examined, but we judge that they are not conspecific. These specimens represent a species of Pannychia that is quite distinct morphologically and genetically from P. moseleyi (Davey et al ., in preparation). In table 1 we detail the significant morphological diagnostic differences between P. taylorae O’Loughlin sp. nov. and P. moseleyi .