Fascaplysinopsis palauensis 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 : 214-216

Fascaplysinopsis palauensis Ekins, Erpenbeck & Hooper sp. nov.

Figures 3 , 7

urn:lsid:zoobank.org:act:71F105FA-D909-4952-9C37-5261E922902E

Material examined. Holotype CASIZ 302698 Oceania, Palau, Hydrographer’s Bank between Peleliu and Angaur, 6.92883°N, 134.20233°E, 24 m, an oceanic bank with very high currents, SCUBA, CRRF #0YYA0337-H, MKB28 , Coll. Patrick Colin, Coral Reef Research Foundation, 15/IV/2011.

Etymology. This species is named after the type locality of the holotype.

Distribution. This species is currently known only from a single specimen from one locality, Hydrographer’s Bank in Palau ( Fig. 3 ).

Description:

Growth form: The lobate morphology consists of multiple lobes or blunt fingers, 20 cm in diameter and about 5 cm in height ( Fig. 7 A ).

Colour: The exterior colour is grey underwater. The interior colour is golden. In 70% ethanol, the exterior is a dark brown, whilst the interior is a dull yellow. The fibres are a burnt orange colour

Oscules: There are a few conules, scattered over the surface. The oscula opening is approximately 2–3 mm in size.

Texture: The sponge is compressible, firm and tough.

Surface: The surface is conulose, the blunt conules are 3–4 mm in height and separated by 3–5 mm. The blunt conules are often formed by several primary fibres coming together. The conules are connected to usually five sometimes four other conules with long curvaceous ridges that rise high above the valleys between them ( Fig. 7 C ).

Ectosomal skeleton: The ectosomal is composed of dark brown membranous skin, which includes some intermittent sand in the upper part of the ectosome ( Fig. 7 D, E ).

Choanosomal skeleton: The choanosome is composed of thick collagenous material, with occasional sand detritus present. The skeleton is a fairly regular radial pattern of large (300–400 μm in diameter) laminated cored primary fibres, these primary fibres are loosely fasciculated in pairs and connected by a reticulated skeleton of usually uncored laminated secondary fibres (80–140 μm in diameter) and tertiary fibres (30 μm in diameter) ( Fig. 7 F ). The secondary and tertiary fibres are usually pithed ( Fig. 7 G–H ).

Ecology. This species from Palau is located off shore in clear waters from a coral bank at a depth of 24 m. The lower surfaces of the lobes are encrusted by epibionts including: red algae, octocorals, ascidians and sponges .

DNA Barcodes. 28S: Holotype CASIZ 302698 ( OX458934 )

Remarks. This new species from the Northern Hemisphere i.e. Palau, can be separated morphologically by the blunt conules formed from several fibres, as well as the large amount of pith present in the secondary fibres.

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 7. Fascaplysinopsis palauensis sp. nov. A. Holotype CASIZ 302698 underwater. B. Holotype CASIZ 302698 on deck. C. Surface of the fixed holotype CASIZ 302698 showing the outer ectosomal membrane and the conule formation with the trace amount of sand in the dermis. D. Cross section through the holotype showing the thin ectosome with trace amount of sand and the collagenous choanosome. E. Dissected primary fibres forming the conules. F. Disassociated fibres, showing the extensive sand coring in the weakly paired fasciculating primary fibres. G. Laminated primary and secondary fibres. H. Coring and pithing of the primary and secondary fibres.