Litophyton folium sp. nov.

(Figs. 80 d-e, 85a-b; 86-88)

Material examined. Holotype NTM C4128, Queensland, Great Barrier Reef, Davies reef, depth 10-15 m, 16 April 1981, coll. Z. Dinesen ; paratypes: NTM C4123, same data as holotype; NTM C4147, Queensland, Great Barrier Reef, Davies reef, depth 15-20 m, 16 April 1981, coll. Z. Dinesen; NTM C4386, Queensland, Great Barrier Reef, Davies reef, depth 15-20 m, 15 April 1981, coll. Z. Dinesen; NTM C10456 GBR 1; Great Barrier Reef, Cockburn reef, 12 December 1990, coll. P. Alderslade.

Description. The holotype is 8 cm high and 8.5 cm wide, the stalk is 1.5 cm long (Fig. 80d). The polyps are up to 0.7 mm wide and high, grouped in conical catkins.

Polyps. With irregular arrangement of sclerites in eight points (Fig. 85a). Abaxially and lateral point sclerites are spindles; abaxially up to 0.40 mm long, with spines and a few distal leaves (Fig. 86a); laterally they are up to 0.20 mm long, with spines. Adaxially there are small, bent rods (Fig. 86b), up to 0.10 mm long. The tentacles have rods and scales (Fig. 86 c-d). The polyp stalk has a few straight rods, up to 0.10 mm long (not depicted). Supporting bundle not projecting or slightly so, composed of spindles, up to 0.70 mm long, with simple tubercles and distally some spines (Fig. 86e).

Surface layer top stalk. Derivatives of capstans, 0.05-0.15 mm long; spindles and unilaterally spinose spindles are also present, up to 0.50 mm long, with simple and complex tubercles (Fig. 86 f-g). The unilaterally spinose sclerites have long spines.

Surface layer base stalk. Capstans, derivatives of capstans, spindles, and unilaterally spinose spindles, mostly with simple tubercles (Fig. 86 h-i). The spines of the spinose sclerites are very long. Capstans 0.05-0.20 mm long; spindles up to about 0.40 mm long.

Interior stalk. Spindles, up to 1 mm long, with pointed ends (Fig. 87b) and simple and complex tubercles (Fig.87c); especially the smaller spindles with one or more side branches (Fig. 87a).

Etymology. The Latin folium, leaf, refers to the leafy point spindles.

Distribution. Great Barrier Reef: Davies reef, Cockburn reef.

Remarks. NTM C4147, NTM C4386, and NTM C10456 (Fig. 80e) have slightly less developed polyp sclerites, seldom with distal leafy appearance (Fig. 88). The surface stalk sclerites of the base of NTM C10456 are less spiny (Fig. 88h) and the internal stalk sclerites are shorter and less branched (Fig. 88j). Sclerite sampling of NTM C10456 was done somewhat above the base of the stalk, causing these differences.

L. debilis (Kükenthal, 1895) (Ternate) (Figs. 69e, 77) resembles this species but has the larger interior stalk spindles also with side branches.

The species also resembles L. darleyensis sp. nov. but has more developed point sclerites, more unilaterally spinose sclerites and shorter interior stalk spindles.

In group V also L. sanctuaryensis sp. nov and L. verrucosum sp. nov. have unilaterally spinose sclerites with long spines. L. sanctuaryensis differs in having much more robust interior stalk sclerites and the smaller ones are less branched. L. verrucosum also has more robust interior stalk sclerites, which are not branched.