Cymbastela sodwaniensis Samaai, Pillay & Kelly, 2009

Samaai, Toufiek, Pillay, Ruwen & Janson, Liesl, 2019, Shallow-water Demospongiae (Porifera) from Sodwana Bay, iSimangaliso Wetland Park, South Africa, Zootaxa 4587 (1), pp. 1-85 : 48

Cymbastela sodwaniensis Samaai, Pillay & Kelly, 2009

( Fig. 19 A–G)

Material examined. SAMC–A24770 (cross-reference TS 884), Ramsay reef, Sodwana Bay, South Africa (27.4466°S; 32.7152°E), 0 3 November 2003, collected by T. Samaai, depth 18 m ; SAMC–A24771 (crossreference TS 937), Seven Mile reef, Sodwana Bay, South Africa (27.4580°S; 32.7141°E), 0 7 November 2003, collected by T. Samaai, depth 20 m.

Other material examined. Holotype. SAM–H5111 (Ts 851): Potholes Five Mile reef, Sodwana Bay, South Africa (27.495°S; 32.6902°E), 0 3 November 2003, collected by T. Samaai, depth 20 m.

Description. Vase-shaped sponge with undulating rounded margins, 55 mm high x 70 mm width; short stalk, 5 mm long, 20 mm wide ( Fig. 19 A–D). Some specimens have multiple undulating lamellae with incised margins. Cup walls thin, somewhat fleshy, 1–8 mm diameter. Surface smooth with nodules, occasionally lamellae. Surface smooth, microscopically hispid, interior of cup with numerous small flush oscules, 0.5–1 mm in diameter. Texture firm, flexible, velvety to the touch, slightly compressible. Colour in life, orange-red; in preservative, beige.

Skeleton ( Fig. 19E, F ). Choanosomal skeleton plumo-reticulate, with poorly differentiated axial and extraaxial architecture. Choanosomal skeleton only slightly axially condensed in the central region; predominately reticulate, with ascending paucispicular plumose tracts curving gradually towards the surface. The outer choanosomal skeleton clearly diverges into plumose ascending multi- or paucispicular tracts interconnected by uni- or paucispicular transverse tracts. These ascending multispicular tracts are encased in a sheath of transparent spongin that is clearly visible under high magnification. The ectosomal skeleton is not specialised, with plumose brushes of choanosomal oxeas protruding through ectosome for short distances, producing microscopic surface conules. Tracts may or may not be interconnected by paucispicular transverse fibres, but usually hidden by diverging spicules.

Spicules. Megascleres ( Fig. 19G ). Oxeas, small, with uniform thickness, usually curved midway, sharply pointed or fusiform, 185 (176–200) µm × 8.5 (8–9) µm, n=10.

Substratum, depth range and ecology. Restricted to shallow coastal coral reef waters, depth 15– 30 m. Substrate is predominately rock or coral, and the sponge is found in areas sheltered from strong currents.

Geographic distribution. Sodwana Bay and Aliwal Shoal, east coast of South Africa.

Remarks. The genus consists of nine species described from Australia and New Caledonia ( Alvarez & Hooper 2002; Alvarez & Hooper 2009). Cymbastela sodwaniensis is the only Cymbastela found outside Australia and New Caledonia and it is readily distinguished from all other species of Cymbastela due to its poorly differentiated choanosome, bright orange colouration and cup-shaped morphology. This is the first record of Cymbastela in South Africa and in the WIO. For further remarks on this species see Samaai et al. 2009.

Key diagnostic characters.

• Sponge vase-shaped and velvety.

• Oxeas only as megascleres.

Figures

FIGURE 19. Cymbastela sodwaniensis Samaai et al., 2009. A-D. In situ; E & F. Skeletal architecture (E, x5; F, x 10); G. Oxeas.