Litophyton fusum, Van, 2020

Van Ofwegen, Leen P., 2020, The genus Litophyton Forskål, 1775 (Octocorallia: Alcyonacea: Nephtheidae) from Australia, Zootaxa 4764 (1), pp. 1-131 : 105-106

Litophyton fusum sp. nov.

( Figs. 85c , 89a , 90-91 )

Material examined. Holotype NTM C4366 , Queensland, Great Barrier Reef, John Brewer reef, depth 10-13 m, 7 February 1981, coll. Z. Dinesen ; paratype; NTM C4075, Queensland, Great Barrier Reef, Rib reef, depth 5-11 m, 27 May 1981, coll. Z. Dinesen.

Description. The holotype is 8 cm high and 11 cm wide, the stalk is very short, almost immediately above the base the colony divides in two stems baring the branches ( Fig. 89a ). The polyps are up to 0.8 mm wide and high, they are grouped in long catkins.

Polyps. With irregular arrangement of sclerites in eight points ( Fig. 85c ). Abaxially and lateral point sclerites are spindles with simple tubercles and spines, abaxially up to 0.50 mm long, laterally up to 0.20 mm long ( Fig. 90a ). Adaxially there are small, curved rods and scales, up to 0.10 mm long, similar to those of the tentacles ( Fig. 90b ). The polyp stalk has straight rods, up to 0.15 mm long ( Fig. 90c ). Supporting bundle not projecting or slightly so, composed of spindles, up to 1.50 mm long, with simple tubercles and one spiny end ( Fig. 90d ).

Surface layer top stalk. Spindles, and unilaterally spinose spindles, up to 1.50 mm long, mostly with complex tubercles ( Fig. 90 e-f).

Surface layer base stalk. A few capstans and derivatives of capstans (not depicted) but mostly spindles and unilaterally spinose spindles, all with simple and complex tubercles ( Fig. 90g , 91 a-b). Capstans 0.10-0.20 mm long; spindles up to about 1.50 mm long.

Interior stalk. Spindles, up to 2 mm long, with simple and complex tubercles ( Fig. 91e ), with pointed ends; many with side branches ( Fig. 91 c-d).

Etymology. The Latin fuses, spool, spindle, refers to the many spindles in the surface layer of the base of the stalk.

Distribution. Great Barrier Reef: John Brewer reef, Rib reef.

Remarks. The paratype has also big interior stalk spindles, but they have no side branches, apparently the base of the stalk is missing.

The species resembles L. snakeensis sp. nov. regarding the many spindles in the surface layer of the base of the stalk, but that species has many scales in the polyps. It resembles L. brachiatum sp. nov. regarding the interior stalk spindles with side branches and the polyp sclerites, but differs from that species in having only a few radiates and derivatives of radiates in the surface layer of the stalk, and no unilaterally spinose spheroids at all.

Figures

FIGURE 85. Lateral views polyp armature of Litophyton species: a-b, L. folium n. sp., a, holotype NTM C4128, b, paratype NTM C10456; c, L. fusum n. sp., holotype NTM C4366; d; L. horseshoeensis, n. sp., holotype NTM C2256; e-f, L. sanctuaryensis n. sp., e, holotype NTM C1387; f, paratype NTM C4383; g. L. swainensis n. sp., holotype NTM C1371; h, L. verrucosum n. sp., holotype NTM C4071.

FIGURE 89. Litophyton type specimens: a, L. fusum n. sp., holotype NTM C4366; b, L. horseshoeensis n. sp., holotype NTM C2256; c-d, L. mollis (Macfadyen, 1936), c, holotype BMNH 1934.3.28.51, d, NTM C2262. Scale at d 1 cm, all others natural size.

FIGURE 90. Litophyton fusum n. sp., holotype NTM C4366; a, abaxial and lateral point spindles; b, adaxial and tentacle sclerites; c, polyp stalk rods; d, supporting bundle spindles; e-f, sclerites of surface layer top of stalk; g, sclerites of surface layer base of stalk. Scale at a also applies to d-e, g; scale at b also applies to c.

FIGURE 91. Litophyton fusum n. sp., holotype NTM C4366; a-b, sclerites of surface layer base of stalk; c-d, spindles of interior base of stalk; e, tuberculation of interior base stalk spindle. Scale at a also applies to c; scale at d also applies to b.