Sycettusa zanzibaris

• Main Authors: Van, Rob W. M., De, Nicole J.
• Format: Other/Unknown Material
• Language: unknown
• Published: 2018
• Subjects: Biodiversity; Taxonomy; Animalia; Porifera; Calcarea; Leucosolenida; Heteropiidae; Sycettusa; Sycettusa zanzibaris; Bird Island; Burton
• Online Access: https://zenodo.org/record/5966758; https://doi.org/10.5281/zenodo.5966758

Sycettusa zanzibaris (Jenkin, 1908) Figs 77a–g, 78a–i Grantessa zanzibaris Jenkin, 1908: 448, figs 98–102; Burton 1959: 180. Material examined. ZMA Por. 11491, Seychelles, Bird Island, off E coast, 3.7167°S 55.2167°E, reef, depth 3 m, snorkeling, coll. R.W.M. van Soest, field nr. NIOP-E stat. 717/ 08, 20 December 1992; ZMA Por. 11566, Seychelles, Amirantes, Île Desnoeufs platform, outer slope, 6.2167°S 53.0167°E, depth 12–15 m, scuba, coll. R.W.M. van Soest, field nr. NIOP-E stat. 738/ 22, 2 January 1993; ZMA Por. 11568, Seychelles, Amirantes, N of D’Arros Island, 5.4°S 53.3167°E, depth 45–55 m, on rhodolite bottom, dredge, coll. R.W.M. van Soest, field nr. NIOP-E stat. 752/ 13, 26 December 1992; ZMA Por. 12438, Seychelles, Amirantes, N of D’Arros Island, 5.4°S 53.3167°E, depth 45–55 m, on rhodolite bottom, dredge, coll. R.W.M. van Soest, field nr. NIOP-E stat. 752/ 11, 26 December 1992. Description. Masses of short tubes (Figs 77a–b), beige-white to light brown in situ and on deck, pale transparent white in alcohol. The specimens have a quite characteristic glassy slippery appearance in alcohol. Size of largest mass up to 2 cm in lateral expansion, 1–2 cm high. Individual tubes up to 5 mm high, 3–4 mm in diameter, with the oscule about 1 mm diameter and surrounded by a thin collar. Consistency cartilaginous. Aquiferous system. Syconoid. Skeleton. (Figs 77c–g) Inarticulate (Figs 77c–d). The cortical skeleton (Fig. 77e) is a mixture of tangential triactines and short banana-shaped diactines, carried by the shortest paired actine and unpaired actine of subcortical pseudosagittal triactines. The inarticulate skeleton is made up of the longer actines of the subcortical pseudosagittal triactines and the unpaired actines of subatrial triactines. The atrial skeleton (Fig. 77f) consists of the paired actines of the subatrial triactines supported by two types of tetractines, smaller with all actines of almost similar length and thickness, and larger with enlarged apical actines protruding far into the atrial lumen. The ...