Ofwegenum coronalucis, McFadden & Benayahu & Samimi-Namin, 2024

McFadden, Catherine S., Benayahu, Yehuda & Samimi-Namin, Kaveh, 2024, A new genus of soft coral (Octocorallia, Malacalcyonacea, Cladiellidae) and three new species from Indo-Pacific coral reefs, ZooKeys 1188, pp. 275-304 : 275

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 ).

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 ).

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 ).

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.

Figures

Figure 1. Distribution of the Ofwegenum gen. nov. species in the Indo-Pacific region. The colour shades represent the different marine realms. Yellow = West Indo-Pacific, blue = Central Indo-Pacific, red = East Africa, green = temperate Australasia; PG = Persian Gulf, AS = Arabian Sea, RS = Red Sea, GO = Gulf of Oman, OM = Oman.

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 C 13089 B O. colli sp. nov. several paratype colonies NTM C 015578 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 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.

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.

Figure 16. Phylogenetic relationships among species of Ofwegenum gen. nov. and other genera of the family Cladiellidae A maximum likelihood (ML) analysis of concatenated mtMutS and 28 S rDNA barcoding loci. Numbers at nodes: ML bootstrap percentage (10,000 ultrafast bootstrap replicates) / Bayesian posterior probability. Asterisks indicate samples that are included in analysis of conserved elements B maximum likelihood analysis of 1,213 conserved element loci (75 % occupancy matrix). All nodes have 100 % bootstrap support and SH-aLRT = 100 unless indicated. All Co _ numbers are SMNHTAU.