Litophyton simplex sp. nov.

(Figs. 42d, 49a, 50)

Material examined. Holotype NTM C3949, Queensland, Great Barrier Reef, Davies reef, depth 10-15 m, 15 April 1981, coll. Z. Dinesen ; paratype NTM C4023, same data as holotype.

Description. The holotype NTM C3949 is 6.5 cm high and 6 cm wide, the stalk is 2 cm high (Fig. 49a). The polyps are up to 0.80 mm wide and 0.95 mm high, and grouped in long catkins.

Polyps. Without clear arrangement of sclerites (Fig. 42d). Abaxial point sclerites are spindles, up to 0.40 mm long, with simple tubercles (Fig. 50a). Scales and rods, 0.03-0.12 mm long, are present laterally and adaxially, and they are also present in the tentacles and polyp stalk (Fig. 50 b-c). Supporting bundle without projecting spindles or one projecting for a maximum distance of 0.10 mm, composed of spindles, up to 1.00 mm long, with simple tubercles (Fig. 51d). Several polyp sclerites have an optically black inner core.

Surface layer top stalk. Spindles and unilaterally spinose spindles, up to 0.50 mm long, with simple and complex tubercles (Fig. 50 e-f).

Surface layer base stalk. Capstans, derivatives of capstans, spindles and unilaterally spinose spindles, all with simple and complex tubercles (Fig. 50 g-h). The spindles are up to 0.50 mm long.

Interior stalk. Spindles, up to 1.00 mm long, with simple tubercles (Fig. 50k), and pointed ends (Fig. 50 i-j).

Etymology. The Latin simplex, simple, referring to the simple tuberculation of the sclerites of this species.

Distribution. Great Barrier Reef: Davies reef.

Remarks. The species resembles L. nigrescens (Roxas, 1933) (Ternate) (Figs. 51, 56a) but differs in having much coarser, sparse tuberculation in the stalk sclerites.