A new genus of soft coral (Octocorallia, Malacalcyonacea, Cladiellidae) and three new species from Indo-Pacific coral reefs Author McFadden, Catherine S. https://orcid.org/0000-0002-8519-9762 Department of Biology, Harvey Mudd College, Claremont, CA 91711, USA mcfadden@hmc.edu Author Benayahu, Yehuda https://orcid.org/0000-0002-6999-0239 School of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, 69978, Tel Aviv, Israel Author Samimi-Namin, Kaveh https://orcid.org/0000-0002-7744-9944 Marine Evolution and Ecology Group, Naturalis Biodiversity Center, P. O. Box 9517, 2300 RA Leiden, Netherlands & Department of Biology, University of Oxford, Oxfordshire, Oxford OX 1 3 SZ, UK & Natural History Museum, Cromwell Road, London SW 7 5 BD, UK text ZooKeys 2024 2024-01-10 1188 275 304 http://dx.doi.org/10.3897/zookeys.1188.110617 journal article http://dx.doi.org/10.3897/zookeys.1188.110617 1313-2970-1188-275 528120A62EC04796B37B5E51FD1FE7AA 3ADC360B3D7D5B46BFD68CD765E7C3F0 Ofwegenum coronalucis sp. nov. Figs 1 , 2A, B , 3H, I , 7 , 8 , 9 , 10A-D , 11 Material examined. Holotype . Oman • Dhofar , Mirbat , Michel's Reef ; 16.9433°N , 54.7300°E ; 25-30 m depth ; 20 January 2022 ; coll. C.S. McFadden and K. Samimi-Namin ; UF 17263 (BOMAN-08362). Paratype . Oman • same data as holotype; SMNHTAU_ Co _39048 (BOMAN-08351) . Other material. Oman • Dhofar , Mirbat , Frankincense ; 16.9662°N , 54.6900°E ; 24-30 m depth ; 19 Jan 2022 ; coll. C.S. McFadden ; UF 15819 (BOMAN-08345) • Dhofar , Mirbat , near Frankincense ; 16.9688°N , 54.6877°E ; 24-29 m depth ; 21 Jan 2022 ; coll. C.S. McFadden and K. Samimi-Namin ; UF15882 (BOMAN-09175) • same collection data as for preceding; UF 15877 (BOMAN-09166) • same collection data as for preceding; in situ photo, microscope slides and molecular data only; BOMAN-09174. Unknown • Aquarium trade, Chicago, IL , USA ; July 2013 ; coll. A. Parrin; SMNHTAU_Co_38223. Description. The holotype consists of several fragments of a colony; the largest is 10 mm in diameter (Fig. 3H ). The colony consists of multiple capitate polyparia on sterile stalks; side branches connect adjacent stalks to one other at the base to form an encrusting mat. Most polyps are contracted, with polyps widely set on the polyparium (Figs 3H , 9A, B ). Figure 2. Morphological details of live Ofwegenum gen. nov. polyps A, B close up of Ofwegenum coronalucis sp. nov., holotype, UF 17263; arrows indicate the concentration of minute sclerites around the mouth opening and base of the tentacles C-F unknown species of Ofwegenum gen. nov. from the aquarium trade. Scale bars: approximately 5 mm (photographs A, B K. Samimi-Namin C-F Daniel Knop). Figure 3. Preserved type colonies of Ofwegenum gen. nov. A O. colli sp. nov., holotype NTM C13089 B O. colli sp. nov. several paratype colonies NTM C015578 C O. aff. coronalucis , SMNHTAU_Co_38223 D O. kloogi sp. nov. holotype SMNHTAU_Co_34426, grooves on polypary are indicated by arrows, distal ends of tentacles protrude from polyp mounds E O. kloogi sp. nov., several paratype colonies SMNHTAU_Co_38299 F O. verseveldti comb. nov., holotype SMNHTAU_Co_25554 G O. verseveldti comb. nov., paratypes, SMNHTAU_Co_25544, grooves on polypary are indicated by arrow H O. coronalucis sp. nov., holotype, UF 17263 I O. coronalucis sp. nov., paratype SMNHTAU_Co_39048). Figure 4. Ofwegenum colli sp. nov., holotype NTM C13089 A sclerites of the coenenchyme and polyp body B sclerites of the tentacles. Figure 5. Ofwegenum colli sp. nov., paratype NTM C3827 A sclerites of the coenenchyme and polyp body B sclerites of the tentacles. Figure 6. Ofwegenum colli sp. nov., paratype NTM C3829 A sclerites of the coenenchyme and polyp body B sclerites of the tentacles. Sclerites of the coenenchyme are spindles and rods up to 0.40 mm long with low, simple tubercles or areas of thickening forming concentric, raised rings (Fig. 7A ). The polyp body contains similar but shorter rods that appear to be arranged 'en chevron' when the polyp is extended (Fig. 2A ). These sclerites are usually blunt and have a crystalline texture at both ends (Fig. 7A ). The length of the sclerites decreases along the polyp body towards the base of the tentacles (Fig. 7A ). Figure 7. Ofwegenum coronalucis sp. nov., holotype UF 17263 A sclerites of the coenenchyme and polyp body B sclerites of the tentacles C sclerites around the polyp mouth opening. Scale at B also applies to C . The tentacles and pinnules contain numerous platelets and flattened rods (i.e., finger-biscuits) up to 0.10 mm long (Fig. 7B ), arranged on the aboral side of the tentacles (Fig. 2A, B ). Some of these sclerites have median constrictions, side notches, or depressions at one or both ends resembling figure-eight shapes (Fig. 7B ). There are also numerous irregularly shaped platelets with side notches or side branches, up to 0.05 mm in length (Fig. 7C ), that are distributed around the mouth and base of the tentacles on the oral side. These sclerites are reflective in light (Fig. 2A, B ). Colour. In life, colonies appear brown with blue-green tentacles. After preservation in ethanol, they are creamy white. Sclerites colourless. Morphological variations. UF 15882 and BOMAN-09174 have slightly thinner spindles and rods both in the coenenchyme and polyp body (Fig. 8A ). In addition, the polyp sclerites have fewer side notches and depressions compared to the holotype (Fig. 8B ). Photos of the live specimens suggest that some of the polyps do not have the reflective sclerites around the mouth (Figs 9E, F , 10C, D ). Figure 8. Ofwegenum coronalucis sp. nov., UF 15882 A sclerites of the coenenchyme and polyp body B sclerites of the tentacles C Sclerites around polyp mouth opening. Scale bars: 0.05 mm ( B, C ). Figure 9. Ofwegenum coronalucis sp. nov. A, B colony and polyps of holotype, UF 17263 C, D colony and polyps of paratype, SMNHTAU_Co_39048 E, F colony and polyps of UF 15882. Scale bars: ~ 50 mm ( A, E ); ~ 5 mm ( B-D, F ) (photographs K. Samimi-Namin). Figure 10. A, B Ofwegenum coronalucis sp. nov., UF 15877 C, D Ofwegenum coronalucis sp. nov., BOMAN-09174 E Ofwegenum kloogi sp. nov. holotype SMNHTAU_Co_34426. (Photos A-D C. S. McFadden E Y. Benayahu). Scale bars: ~ 5 mm ( A-D ); 5 cm ( E ). Figure 11. Ofwegenum aff. coronalucis SMNHTAU_Co_38223 A sclerites of the coenenchyme and polyp body B sclerites of the tentacles. SMNHTAU_Co_38223 comes from the aquarium trade in the U.S. Its commercial source is assumed to be Jakarta, Indonesia (A. Parrin, pers. comm. 12 Aug 2013), but the original collection locality remains unknown. This colony is tentatively assigned as O. aff. coronalucis based on its sclerite features and genetic similarity to this species (Fig. 16 ). However, it differs from the other material in having a blue colour in the coenenchyme and shorter tentacle sclerites up to 0.07 mm long. Such differences might be due to a prolonged exposure to the artificial aquarium environment. Remarks. Ofwegenum coronalucis sp. nov. differs from its congeners in having irregularly shaped sclerites with side notches or side branches around the polyp mouth that reflect light (Figs 2A, B , 7C , 8C ). Additionally, the tentacle platelets have narrow median constrictions compared to the other species (Figs 7B , 8B ). Distribution. Oman. Etymology. The species name is from the Latin corona (crown) and lucis (of light), referring to the reflective ring of sclerites around the polyp mouth in the live specimens.