Litophyton mollis ( Macfadyen, 1936 )

Van Ofwegen, Leen P., 2020, The genus Litophyton Forskål, 1775 (Octocorallia: Alcyonacea: Nephtheidae) from Australia, Zootaxa 4764 (1), pp. 1-131 : 107-115

Litophyton mollis ( Macfadyen, 1936)

( Figs. 89 c-d, 94-96)

Nephthya mollis Macfadyen, 1936: 57 , figs 9-10, pl. 5 Fig. 6 ( Australia, GBR, Low lsles).

Material examined. Holotype BM 1934.3.28.51; NTM C88-NTM C89 , Queensland, Great Barrier Reef, Erskin Is. , depth 1 m, 4 April 1977, coll. P. Alderslade; NTM C266 , broken up colony, Queensland, Broadhurst reef, March 1976, coll. G. Coll; NTM C798, March 1978, coll. D. Schubot; NTM C1386 , Queensland, Swain reefs, Sanctuary reef, 13 November 1980, coll. P. Alderslade; NTM C1475-NTM C1481 , Queensland, Central Reef , depth 2/ 3 m, 5 November 1980, coll. P.Alderslade; NTM C2241-NTM C2243, Queensland, Masthead reef, 27 October 1974, coll. P. Alderslade; NTM C2244 , Queensland, Moore reef, Bommie , surface, March 1978, coll. P. Alderslade; NTM C2258, Queensland, Northwest Island, depth 7 m, 10 October 1978, coll. P. Alderslade; NTM C2262 ; Queensland, Northwest Island , depth 7 m, 10 October 1978; coll. P. Alderslade; NTM C2829 , coll. Z. Dinesen; NTM C4000 , Queensland, Great Barrier Reef, Rib reef, depth 10-15 m, coll. Z. Dinesen; NTM C05390 , cf. albida, Queensland, Great Barrier Reef, Darley reef, 25 November 1982, coll. G. König; NTM C10463 , Queensland, Great Barrier Reef, Cockburn reef, 10 December 1990, coll. P. Alderslade.

Re-description. The holotype is 11.5 cm high and 10 cm wide, the stalk is 3 cm long ( Fig. 89c ). The polyps are up to 0.8 mm wide and high, grouped in conical catkins.

Polyps. With irregular arrangement of sclerites in eight points ( Fig. 94a ). Abaxial and lateral point sclerites are spindles with simple tubercles and spines, largest present abaxially, up to 0.40 mm long, laterally they are up to 0.15 mm long ( Fig. 94b ). Adaxially there are small scales, similar to those of the tentacles, up to 0.10 mm long ( Fig. 94c ). These small rods also are present on the adaxial side of the polyp stalk. Supporting bundle not projecting, composed of spindles, up to 0.50 mm long, with simple tubercles ( Fig. 94d ).

Surface layer top stalk. Capstans and derivatives of capstans, 0.05-0.10 mm long; spindles and unilaterally spinose spindles are also present, up to 0.35 mm long, with simple tubercles ( Fig. 94e ). Towards the interior a few slightly stouter spindles occur ( Fig. 94f ).

Surface layer base stalk. Capstans, derivatives of capstans, spindles, and unilaterally spinose spindles ( Fig 94g ). Capstans 0.05-0.10 mm long; spindles up to about 0.30 mm long. Towards the interior these sclerite types become slightly bigger with less dense tuberculation ( Fig. 94h ).

Interior stalk. Spindles, up to 0.75 mm long, with pointed ends and simple and complex tubercles and some irregular, branched forms ( Fig. 94 i-j).

Distribution. Great Barrier Reef: Erskin Island, Broadhurst reef, Sanctuary reef, Central Reef, Masthead reef, Moore reef, Northwest Island, Rib reef, Darley reef, Cockburn reef.

Remarks. The differences from L. legiopolypum ( Verseveldt & Alderslade, 1982) are small. L. mollis has fewer rods in the polyps and the internal stalk spindles are less branched.

L. amboinensis ( Burchardt, 1898) from Ambon ( Indonesia) ( Fig. 97a ) also resembles L. mollis but has overall more tuberculated sclerites, polyp spindles are more spiny, and interior base spindles are smaller. ( Fig. 98 ).

NTM C2262 ( Fig. 89d ) has been used for producing SEM images of the sclerites ( Figs. 95-96 ).

NTM C1386, NTM C1475-NTM C1481 were checked with temporary slides only.

Figures

FIGURE 6. Litophyton dipensis n. sp., holotype NTM C362; a, abaxial point spindles; b, lateral point spindle; c, tentacle scales; d, polyp stalk rods; e, supporting bundle spindles, two partly; f-g, sclerites of surface layer top of stalk. Scale at b also applies to c-d.

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 94. Litophyton mollis (Macfadyen, 1936), holotype BMNH 1934.3.28.51; a, lateral view polyp armature; b, abaxial and lateral point spindles; c, adaxial and tentacle sclerites; d, supporting bundle spindle, partly; e, sclerites of surface layer top of stalk; f, spindle of interior of top of stalk; g, sclerites of surface layer base of stalk; h, sclerites of deeper coenenchyme of base of stalk; i-j, spindles of interior base of stalk. Scale at b also applies to d-i.

FIGURE 95. Litophyton mollis (Macfadyen, 1936), NTM C2262; a, abaxial point spindles; b, lateral point spindles and adaxial and tentacle sclerites; c, tentacle scales; d, polyp stalk rods; e, supporting bundle spindle; f-g, sclerites of surface layer top of stalk; h, sclerites of surface layer base of stalk. Scale at a also applies to e, g; scale at b also applies to f, h; scale at c also applies to d.

FIGURE 96. Litophyton mollis (Macfadyen, 1936), NTM C2262; a, sclerites of surface layer base of stalk; b-c, spindles of interior base of stalk; d, tuberculation of interior base stalk spindles. Scale at a also applies to c.

FIGURE 97. Litophyton type specimens: a, L. amboinensis (Burchardt, 1898), holotype MZS NS 158; b-c, L. sanctuaryensis n. sp., b, holotype NTM C1387; c, paratype NTM C4383; d, L. swainensis n. sp., holotype NTM C1371; e-f, L. verrucosum n. sp., e, holotype NTM C4071; f, paratype NTM C3978.

FIGURE 98. Litophyton amboinensis (Burchardt, 1898), holotype MZS NS 158; a, lateral view polyp armature; b, abaxial and lateral point spindles; c, adaxial and tentacle scales; d, supporting bundle spindle, partly; e, sclerites of surface layer top of stalk; f, sclerites of interior of top of stalk; g, sclerites of surface layer base of stalk; h-i, spindles of interior base of stalk; j, tuberculation of interior base stalk spindle. Scale at g also applies to b, d-f, i-j.