Trididemnum strigosum Kott, 1980

Trididemnum strigosum Kott, 1980 View in CoL

(Fig. 119F)

Trididemnum strigosum Kott, 1980: 8 View in CoL , figs 9; 10, pl. 3-3. Type locality: Philippines; 1981: 188, Fiji. — Monniot C. & Monniot F. 1987: 22, fig. 4A-D, Polynesia.

MATERIAL EXAMINED. — Palau. KB Channel, Airai on sea grass, 7°19.35’N, 134°31.73’E, 0.5 m, 20. VI.1996 ( MNHN A2 TRI 134).

DESCRIPTION

This species has algal cells embedded in the tunic. The colonies are small round or oval patches, grouped in clusters. The colour is green to pale green (Fig. 119F), the intensity depending on the abundance of spicules in the superficial layer of the colonies. There is generally a single common cloacal aperture in the centre of each colony. There are accumulations of dark brown bodies in the abdominal layer.

The zooids are extremely small. They have six sharp oral lobes. The cloacal aperture is a wide transverse slit. The leaf-like lateral thoracic organs protrude at the level of the second stigmata row. There is a short retractor muscle.

The abdomen is the same size as the thorax and has a single testis follicle. The larvae contain algal cells but are not fully developed. The spicules are stellate with a few short rays.

REMARKS

This species, first collected in the Philippines, then in Fiji and Polynesia, is now recorded in Palau. The species probably has a wide distribution in the western Pacific region, but is rather inconspicuous with its small colonies.