Kebira spec.

Figs 90a–g

Material examined. ZMA Por. 10379b, Seychelles, Mahé, E coast, N of Moyenne Island, 4.6167°S 55.5167°E, depth 1–7 m, reef, snorkeling, coll. R.W.M. van Soest, field nr. NIOP-E stat. 606, 10 December 1992.

Description. The specimen is small and tubular (Fig. 90a), about 1.5 cm high, 0.5 cm in diameter, with a narrow apical oscule. Color in alcohol dirty white. Surface smooth and shining, due to a thick surface armor of tangential giant diactines.

Aquiferous system. Leuconoid.

Skeleton. In cross section there is a thin cortical layer of triactines with long unpaired actines carried by a thick mass of tangentially arranged giant diactines. The choanosome is a mass of triactines traversed in places by short tracts of nail-shaped triactines. The atrial skeleton is a layer of tri- and tetractines with short unpaired actines and straight paired actines.

Spicules. (Figs 90b–g) Giant diactines, nail-shaped triactines, large triactines with long unpaired actines, small tri- and tetractines with short unpaired actines.

Giant and smaller diactines (Figs 90b), fusiform, curved, 105– 869 – 2520 x 7.5– 37.1 –84 µm.

Nail-shaped triactines (Figs 90c,c 1), fusiform, with one end poined and the opposite end with two tiny actines, usually more or less symmetrical; unpaired actine 252– 503 –781 x 8.5– 9.9 –12 µm, paired actines 3– 6.8 – 15 x 2.5– 4.2 –6 µm.

Triactines with long unpaired actines and flaring paired actines (Fig. 90d); unpaired actines 292– 348 –384 x 10 – 17.8 –24 µm, paired actines 226– 297 –342 x 9 – 18.4 –23 µm.

Tetractines (Fig. 90e), with short unpaired actines and straight paired actines; unpaired actines 31– 49 – 61 x 8 – 10.3 –12 µm, paired actines 69– 192 –231 x 8 – 11.6 –14 µm, apical actines 3– 25 – 32 x 3 – 7.9 –10 µm.

Triactines (Fig. 90f), with short unpaired actines and straight paired actines; unpaired actines 30– 46 – 63 x 7 – 10.3 –12 µm, paired actines 71– 188 –234 x 8 – 10.9 –12 µm.

Distribution and ecology. Seychelles, shallow-reef locality.

Remarks. Although this specimen shares the possession of atrial tetractines with Kebira tetractinifera sp.nov., it shares also features with K. uteoides such as a dense layer of tangential diactines, twice as long as those of K. tetractinifera sp.nov. Further research is necessary to establish the value of these features for distinction of additional taxa in Kebira .

Unfortunately, our attempt to obtain a 28S sequence of the specimen failed.