Theonella swinhoei Gray, 1868

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 : 27-29

Theonella swinhoei Gray, 1868

( Fig. 10 A–H)

Synonymy

Dactylocalyx prattii Bowerbank, 1869: 89 , pl. v, figs 6–11.

Theonella pratti ( Bowerbank, 1869) : 89, pl. v, figs 6–11.

Theonella swinhoei Gray, 1868: 566 , fig. 1; Zittel, 1878a: 87, pl. 1: 9b; Lendenfeld, 1903: 126; Thiele, 1900: 53, pl. 3: 3–4; Wilson, 1925: 448; Lévi, 1958: 5, fig. 1; Lévi, 1961 a: 4, fig. 1; Vacelet & Vasseur, 1971: 58, fig. 1; Lévi & Lévi, 1989: 56, fig. 24; Pulitzer-Finali, 1993: 261; (?) Gruber, 1993: 44, pl. 10: 7–8, pl. 11: 1–2.

Theonella sp., Kelly in Richmond, 2010: 118–119.

Material examined. SAMC–A24735 (cross-reference TS 943 & Saf03-Sod16), Ramsay reef, Sodwana Bay (27.4466°S, 32.7152°E), South Africa, 0 3 November 2003, collected by T. Samaai, depth 18 m. SAMC–A24736 (cross-reference TS 848 & Saf 03-Sod 25), Five Mile reef, Sodwana Bay (27.495°S, 32.6902°E), South Africa, 0 3 November 2003, collected by T. Samaai, depth 20 m.

Description. Massive, erect, tubular domes with coalescent digits, 45 × 25 × 80 mm in diameter, base attached to the rocky substrate ( Fig. 10A, B ). Surface smooth with a single large oval-shaped oscule, 5–9 mm in diameter located in the middle of the tubular dome. Texture firm, velvety to the touch, not compressible, difficult to break. Colour in life maroon-brown, interior off whitish and in preservative, beige.

Skeleton ( Fig. 10C, D ). Choanosomal skeleton is composed of regular tetraclone desmas, which may be smooth or poorly tuberculated. Ectosomal spicules are differentiated phyllotriaenes with a relatively long and slender clads, or conversely, relatively massive flattened clads in various parts of the sponge. Those with narrow clads occur mostly in the inhalant areas on the outer sponge surface; while those with the massive clads occur mostly in the choanosome. Clads are sparsely tuberculated. There are numerous microscleres occurring on the dermal membranes as well as in the ectosome.

Spicules. Megascleres ( Fig. 10 E–G). Phyllotriaenes 560 (420–750) µm, n = 10 in diameter; Tetraclone desmas, smooth, branched and strongly tuberculated: 360 (325–420) µm, n = 10; Strongyles, slightly curved (sometimes oxeas) being either rounded or hastately pointed, 511 (390–593) × 5 (5) µm, n = 10. No tylote forms present in the samples. Microscleres ( Fig. 10H ). Acanthorhabds, 5 (3–8) × 2 (2) µm, n = 10.

Substratum, depth range and ecology. The sponge is found in shallow waters up to 30 m growing in fairly open reefs exposed to currents.

Geographic Distribution. Widely distributed in the Western Indian and Indo-Pacific Oceans.

Remarks. This species is a well-defined and was first described by Gray (1868) from Taiwan and later by Sollas (1888) from Manila ( Philippines) and recorded by Van Soest (1990) from Indonesia. This sponge is widely distributed in the Indo-Pacific Ocean ( Pisera & Lévi 2002; Ilan et al. 2004; Van Soest et al. 2017). A useful description of this species is given by Sollas (1888), Lévi (1958) and the description of the genus (and therefore the species) type as appears in Pisera & Lévi (2002).

Pulitzer-Finali (1993) described T. swinhoei from Kenya, while Lévi (1958) and Ilan et al. (2004) recorded the species from the Red Sea and Arabian Coasts respectively. One of Pulitzer-Finali’s specimens (MBA 262) however, is considered here as T. conica (own observation) because the specimen has a blue interior and exterior colouration typical to that of T. conica . All these descriptions (including the type species description) ( Gray 1868; Pisera & Lévi 2002) agree closely to T. swinhoei described here. The type specimens have similar external morphologies to the sponge described, viz. a coalesced form being either massive cup-shape or cylindrical, brownish colouration and having one single osculum located on the apex of the sponge. The type species however, differ in spicule dimensions in having larger strongyles (700–900 × 9–11 µm), smaller phyllotrianes (460–560 µm in diameter) and tetraclone desmas (325–369 µm) on average. These specimens conform closely in morphology, colouration and skeletal features to the type description as appears in Gray (1868) and Pisera & Lévi (2002).

Figures

FIGURE 10. Theonella swinhoei Gray, 1868. A–B. In situ; C & D. Skeletal architecture (C, x5; D, x 10); E. Strongyles; F. Tetraclone desmas; G. Phyllotriaenes; H. Acanthorhabd.