Rubrafasciculus cerasus Ekins, Erpenbeck & Hooper, 2023

Ekins, Merrick, Erpenbeck, Dirk, Debitus, Cécile, Petek, Sylvain, Mai, Tepoerau, Wörheide, Gert & Hooper, John N. A., 2023, Revision of the genus Fascaplysinopsis, the type species Fascaplysinopsis reticulata (Hentschel, 1912) (Porifera, Dictyoceratida, Thorectidae) and descriptions of two new genera and seven new species, Zootaxa 5346 (3), pp. 201-241 : 226-230

Rubrafasciculus cerasus Ekins, Erpenbeck & Hooper sp. nov.

Figures 13–16

urn:lsid:zoobank.org:act:CD47671A-C791-42D2-B857-06E1F4BDB30B

Fascaplysinopsis reticulata : in part Bergquist 1995:17–18, Fig. 9 ; Cook & Bergquist 2002: Fig. 5 F

Not: Fascaplysinopsis reticulata : in part Bergquist 1980, Figs. 3 A , 16 A–B ; Cook & Bergquist 2002: Fig. 5. C–D Not: Aplysinopsis reticulata Hentschel, 1912: 437–439 , Pl. XV (1), XVI (9)

Fascaplysinopsis cf. reticulata: Mai et al. 2019

Fascaplysinopsis (cf.) reticulata : in part Erpenbeck et al. (2020) Suppl. Data

Dysidea sp. (OTU QM2669): Petek et al. 2017

Eponges de Mer. OPT-French Polynesia, 100f stamp, first day cover (see Fig. 15 )

Material examined. Holotype QM G314831 , Alcyonarian Point , Hook Island, Whitsunday Group, Queensland, Australia, 20.06553 oS, 149.92346 oE, 15 m, many coral bommies caves and overhangs, silty numerous soft corals, SCUBA, Coll. S.D. Cook, J.D. Kennedy, C.L. Adams, G. Wörheide, & D. Edson, 3/VI/1999.

Paratypes: QM G307568 , Erskine Island , Capricorn-Bunker Group, Great Barrier Reef, Queensland, Australia, 23.5°S, 151.7683°E, 14 m, back reef , SCUBA, Coll. J.N.A. Hooper, S.D. Cook, J.A. Kennedy & P.A. Tomkins, 12/VIII/1996 ; QM G314909 , Cateran Bay , Border Island, Whitsunday Group, Queensland, Australia, 20.15258°S, 149.04233°E, 30 m, fringing coral reef , SCUBA, Coll. Coll. S.D. Cook, J.A. Kennedy, C.L. Adams, G. Wörheide, & D. Edson, 4/ VI /1999; QM G305642 , Frigate Cay, NW side, Swain Reefs , Queensland, Australia, 21.73361°S, 152.41778°E, 27 m, back reef slope , SCUBA, Coll. J.N.A. Hooper, S.D. Cook, J.A. Kennedy & P.A. Tomkins, 27/VII/1995 ; QM G310636 , Scawfell Island , Queensland, Australia, 20.875°S, 149.575°E, 22 m , SCUBA, Coll. Australian Institute of Marine Science & National Cancer Institute, Q 66C1787-J, 10/XI/1988 .

Other material. QM G305474 , Gannet Cay , Swains Reef, Queensland, Australia, 21.96861°S, 152.4675°E, 23 m, coral reef, SCUBA, Coll. J.N.A. Hooper, S.D. Cook, J.A. Kennedy & P.A. Tomkins, 24/VII/1995 ; QM G314745 , Little Lindeman Island , Whitsunday Group, Queensland, Australia, 20.42206°S, 149.04266 o E, 22m, small coral bommies , SCUBA, Coll. S.D. Cook, J.A. Kennedy, C.L. Adams, G. Wörheide, & D. Edson, 2/ VI /1999; QM G315278 , Round Reef , Great Barrier Reef, Queensland, Australia, 19.96073°S, 149.62126°E, 20 m, back reef , SCUBA, Coll. S.D. Cook, J.A. Kennedy, C.L.Adams, G. Wörheide, & D. Edson, 6/ VI /1999; QM G315421 , Chauvel Reef , Great Barrier Reef, Queensland, Australia, 20.82564°S, 150.33549°E, 19 m, back reef , SCUBA, Coll. S.D. Cook, J.A. Kennedy, C.L. Adams, G. Wörheide, & D. Edson, 7/ VI /1999; QM G317097 , Curacoa Channel , Palm Islands, Queensland, Australia, 18.66233°S, 146.53979°E, 20 m, flat silty substrate , SCUBA, Coll. C. Adams, on RV James Kirby , 1/IV/2000 ; QM G318149 , un-named reef, Pompey Group , Queensland, Australia, 21.16217°S, 151.35201°E, 27 m, coral reef , SCUBA, Coll. S.D. Cook, J.A. Kennedy, G. Wörheide & W. Delaney, 14/III/2000 ; QM G318295 , Hard Line Reefs , Great Barrier Reef, Queensland, Australia, 20.96250°S, 151.30133°E, 18 m, flat, silty sand , SCUBA, Coll. S.D. Cook, J.A. Kennedy, G. Wörheide & W. Delaney, 16/III/2000 ; QM G318349 , Pompey Reefs , small unnamed reef, Queensland, Australia, 21.12400°S, 151.13066°E, 27 m, sloping reef with outcrops , SCUBA, Coll. S.D. Cook, J.A. Kennedy, G. Wörheide & W. Delaney, 17/III/2000 ; QM G303895 , Triangle Reef , Hook Reef, Whitsunday group, Queensland, Australia, 19.81694°S, 149.10139°E, 31 m, sheer cliff to 35m depth , SCUBA, Coll. J.N.A. Hooper, & L.J. Hobbs, 10/12/1993 ; QM G330344 , Great Barrier Reef , Queensland, Australia, 18.535°S, 146.565°E, 31.3 m, Trawl, Coll . CSIRO, Sea Bed Diversity Project on RV Gwendoline May , SBD502461, 27/11/2003 ; QM G317478 Merv’s Reef , Swain Reefs, Queensland, Australia, 21.88747°S, 152.34737°E, 30 m, back reef , SCUBA, Coll. J.N.A. Hooper, S.D. Cook, J.A. Kennedy, D. Edson, & G. Wörheide, 6/II/2001 ; QM G317525 , Reef 21-505, Swain Reefs, Queensland, Australia, 21.70532°S, 152.34019°E, 21 m, back reef , SCUBA, Coll. J.N.A. Hooper, S.D. Cook, J.A. Kennedy, D. Edson, & G. Wörheide, 7/II/2001 ; QM G317602 , Reef 21-490, Swain Reefs, Queensland, Australia, 21.60512°S, 152.36989° E, 17 m, back reef , SCUBA, Coll. J.N.A. Hooper, S.D. Cook, J.A. Kennedy, D. Edson, & G. Wörheide, 8/II/2001 ; QM G317718 ,°utside entrance to Star Reef lagoon, Swain Reefs, Queensland, Australia, 21.49818°S, 152.41446°E, 15 m, back reef , SCUBA, Coll. J.N.A. Hooper, S.D. Cook, J.A. Kennedy, D. Edson, & G. Wörheide, 10/II/2001 ; QM G317575 , Reef 21-490, Swain Reefs, Queensland, Australia, 21.61400°S, 152.34705°E, 20 m, back reef, 100% coral cover, flat bottom with occasional small bommies to 1.5m high , SCUBA, Coll. J.N.A. Hooper, S.D. Cook, J.A. Kennedy, D. Edson & G. Wörheide, 8/II/2001 ; QM G315468 , Unnamed reef on inner side of Pompey Reefs, Queensland, Australia, 21.49563°S, 151.16325°E, 26.2 m, back reef , SCUBA, Coll. S.D. Cook, J.A. Kennedy, C.L. Adams, G. Wörheide, & D. Edson, 8/ VI /1999; QM G314857 , Pinnacle Point , Hook Island, Whitsunday Group, Queensland, Australia, 20.06058°S, 148.96106°E, 18 m, fringing reef , SCUBA, Coll. S.D. Cook, J.A. Kennedy, C.L. Adams, G. Wörheide, & D. Edson, 3/ VI /1999; QM G333241 , Rangiroa , Tuamotu, French Polynesia, 15.24733°S, 147.73805°W, 18 m , SCUBA, Coll. B. Bourgeois, Institut De Recherche Pour Le Developpement , P319, 22/ V /2011; QM G333299 , Anuanuraro , Tuamotu, French Polynesia, 20.42323°S, 143.54883°W, 68 m , SCUBA, Coll. J. Butcher, Institut De Recherche Pour Le Developpement , P237, 29/IV/2011 . R. cf. cerasus: QM G 312776, Nukubalavu , Taveuni, Fiji, 16.7503°S, 179.78556°E, 42 m , SCUBA, Coll. J.N.A. Hooper, NCIOCDN4153 X, 28/X/1996 ; QM G324601 , Laukoto Lailai , Vanua Levu, Fiji, 16.63678°S, 178.49253°E, 6–22.9 m , SCUBA, Coll. J.L. Menou, J. Butscher, S. Petek, C. Payri & G, Lasne , R3219 , 10/ V /2007; QM G331054 , Raiatea , Society Islands, French Polynesia, 16.83122°S, 151.34708°W, 45 m, barrier reef pass, soft to steep sandy slope with fragments , SCUBA, Coll. C. Debitus, P60, 16/VIII/2009 ; QM G304688 , Iles Chesterfield , Pacific Ocean, 20.96833°S, 158.57667°E, 40 m , SCUBA, Coll. J.L. Menou, R1344 , 21/VII/1984 ; QM G324365 , Malaita Nord , Lahau Lagoon, Solomons, 8.4182°S, 160.830583°E, 40 m , SCUBA, Coll . IRD, R3165 , 9/VII/2004 ; CASIZ 300177 , Oceania , Palau, reef east of Koror, west side of Uchelbeluu (Sea Bear Site), 7.2735°N, 134.5238°E, 10 m , SCUBA, CRRF # OCDN5079 -G, Coll. Coral Reef Research Foundation, 16/II/1998 .

Etymology. cerasus L., f., cherry

Distribution. This species is widely distributed in the southwest Pacific, ranging from Queensland, Australia, Chesterfield Island, Territory of New Caledonia, Fiji,Society andTuamotuArchipelagos and French Polynesia ( Fig.13 ).

Description:

Growth form: Lobate, massive, with a few apical fistules, often only the fistules are showing above the silty/ sand substrate. The fistules are 8 to 22 mm in height (average 15 mm). The preserved holotype is 8 cm wide, 4.5 cm thick and 8.7 cm in height ( Figs. 14 A–B , 16 A ).

Colour: Fistules and body above the substrate is cherry red to red brown underwater and on deck, the body under the debris is cream. In 70% ethanol, the fistules are often brown to grey, whilst the main body is a beige to tan exterior, with a yellow to beige interior with red fibres.

Oscules: Apical on fistules ( Fig. 14 B ). The 1–2 mm in diameter oscules collapse after removal from water. There are also uncommon, scattered, random 2–3 mm in diameter oscules on the body surface.

Texture: Firm barely compressible, but the fistules are very soft and compressible.

Surface: Conulose, conules 2–3 mm high and usually 2–4 mm but can be up to 10 mm apart interconnected by ridges ( Fig. 14 B–C ).

Ectosomal Skeleton: Clear membranous surface, over a thick well-defined sand and detritus layer (0.750 mm thick) in the lower part of the ectosome ( Fig. 14 D ). However, in the fistules, the sand is often under both the exterior ectosomal layer and the aquiferous channels, thus it can form a double wall enclosing the supporting fibres, of a total of 1.5 mm ( Fig. 14 G ). The membranous fistules have substantially less sand detritus, however the body has large sand particles subectosomally. The ectosome is thin and membranous, but difficult to physically separate from the choanosome. It also difficult to visually separate from the choanosome because of the similar colour of the collagen (mustard yellow) in both regions. The ectosome can often be visually separated from the choanosome under the dissection microscope by the presence of the subectosomal sand/detritus armouring. The sand/detritus layer is thicker in some areas (up to 0.7 mm) and non-existent in other areas such as near ostial pores.

Choanosomal Skeleton: Irregularly branching, widely spaced primary fibres ( Fig. 14 F–G ). Fibres do not form regular meshes. Primary fibres are laminated and cored with detritus (300–1000 μm in diameter), secondary fibres are laminated and often cored (80–200 μm in diameter). Tertiary fibres can sometimes also be cored (10–50 μm in diameter). Fibres also usually have detritus that is cemented to the outside of the fibres almost forming an armour. The skeleton often presents as a lattice of indistinguishable primary, secondary and tertiary fibres. This forms a web cementing in the sand detritus ( Fig. 14 E ). In this case, the primary and secondary fibres are difficult to distinguish, except in the fistules. The primary fibres ascend and converge to form the fistules with the web of secondary fibres. Mesohyl collagen is moderately dense, granular/vaculose and contains sparsely distributed sand grains. The body has many aquiferous channels radiating up from the base, approximately 3 mm in diameter.

Ecology. This species is a semi burrowing to massive sponge associated with sandy habitats on or between reefs at 10 to 68 m in depth. The sponge may have epibionts on the surface including: bryozoans, ascidians, sponges, hydroids and algae.

DNA Barcodes.

28S: Holotype QM G314831 ( OX458936 ), QM G333241 ( OX458945 ), QM G333299 (LR700202); R. cf. cerasus: QM G 331054 (LR699491), QM G312776 ( OX458946 ), QM G324601 ( OX458947 ), CASIZ 300177 ( OX458937 ).

ITS: Holotype QM G314831 (LR700208), QM G333241 (LR700209), QM G333299 ( OX458949 ); R. cf. cerasus: QM G 331054 (LR699342).

Remarks. The inclusion of large amounts of interstitial sand, which is incorporated into all of the fibres, makes sectioning more difficult than other unarmoured sponges. The amount of sand incorporated is determined by the habitat of the sponge, i.e. sponges burrowed into the sand have higher sand concentrations in the fibres than those massive sponges on the reef. Future collections from the Pacific may reveal the differing habitats confer conspecific, at this time we shall group them as one species. The specimens collected from Fiji i.e. QM G312776 and QM G324601, showed morphological difference from other specimens in this species by the lack of sand deposition on the outside of the fibres ( Fig. 16 E–F ). In addition, the lack of fistules, and the extremely heavy fasciculation and anastomosis of the primary and secondary fibres in QM G312776, separate it from the other examined specimens. Due to molecular differences to R. cerasus , and in the absence of discriminating morphological characters we regard these Fijian specimens as R. cf. cerasus , until the species structure is further investigated. Another specimen QM G331054, is burrowed in the sand habitat, but it lacks the sand encrusting on the outside of fibres. It has coring in the secondary fibres and also lacks the obvious fasciculations and anastomosing of the secondary and tertiary fibres that are present in the other specimens. There were also specimens from the South Pacific (i.e. G304688, QM G324365 and CASIZ 300177) that have characteristically strong cored primary fibres with light fasciculations and external sand coating of the fibres. The fibres have only a few joining fibres, leaving the junctions clean and uncluttered ( Fig. 16 F ). In addition, this species has a thicker subectosomal sand armouring (see Fig. 16 D ).

The chemical compounds fascaplysine and palauolide were isolated from this species ( Mai et al. 2019).

Figures

FIGURE 3. Distribution of Fascaplysinopsis reticulata, Fascaplysinopsis palauensis sp. nov., Fascaplysinopsis klobos sp. nov. and Fascaplysinopsis ronquinni sp. nov. Base map modified from freevectormaps.com.

FIGURE 5. Fascaplysinopsis reticulata (Hentschel, 1912) Yellow form. A. QM G325372 on deck immediately after trawling, showing colouration and epibionts. B. QM G325372 immediately after thawing. C. QM G325372 close up of B showing the large conules and the membranous collagen with a plastic like appearance between them. D. QM G325372 fixed showing the sharp conules and membranous valleys. E. Digested tissue of QM G325372, showing the large primary fibres arising in parallel and the secondary fibres bridging the large spaces. F. Digested tissue of QM G325372, showing the coring in the primary fibres and uncored secondary fibres. G. QM G325372 fine tertiary fibres between the secondary fibres. H. Microscope transverse section of QM G325372 showing cored primary fibres, some secondary fibres showing pith and the tertiary fibres (arrow) in the collagenous matrix. I. Microscope transverse section of QM G325372 showing fasciculating primary fibres connected by secondary fibres. J. Microscope cross section of QM G325444 through the primary fibres, showing secondary and tertiary fibres.

FIGURE 9. Fascaplysinopsis ronquinni sp. nov. A. Holotype QM G339083 on deck immediately after collection, and B. fixed. C. Surface of the holotype showing the primary fibres emerging through the ectosome. D. Primary fibres cored with bryozoan and isopod scales. E. Heavily laminated primary, secondary and tertiary fibres. F. Laminated fibres showing the pigmentation.

FIGURE 13. Distribution of Rubrafasciculus cerasus sp. nov. and Rubrafasciculus fijiensis sp. nov. Base map modified from freevectormaps.com.

FIGURE 14. Rubrafasciculus cerasus sp. nov. A. Holotype QM G314831 underwater. B. Holotype QM G314831 on deck immediately after collection. C. The external surface of the fixed holotype QM G314831. D. A longitudinal section through the holotype QM G314831. E. Partial digestion of the holotype QM G314831, showing the sand incorporated in and around the fibres, and the thick collagenous matrix of the mesohyl. F. Primary fibre the holotype QM G314831 showing the sand within and external to the fibres. G. Fasciculation of the primary fibres, with supportive secondary fibres the holotype QM G314831. H. Microscope section of the holotype QM G314831 showing the heavy coring of the primary fibres and some coring in the laminated secondary fibres and the large network of small fibres.

FIGURE 15. Rubrafasciculus cerasus sp. nov. A. QM G333241 underwater. B. A copy of the sponge used in a postage stamp by OPT-French Polynesia.

FIGURE 16. Rubrafasciculus cf. cerasus sp. nov. A. QM G306488 underwater.B. CASIZ 300177 underwater.C. QM G306488 preserved, exterior surface and interior surface. D. QM G306488 surface, showing the transparent membrane and the thick sand armouring of the ectosome and the collagenous choanosome. E. QM G306488 Cored primary fibres and the uncored secondary and tertiary fibres of the holotype. F. QM G306488 Magnified section showing the thick cored primary fibres and the uncored secondary and tertiary fibres of the holotype.