The genus Litophyton Forskål, 1775 (Octocorallia: Alcyonacea: Nephtheidae) from Australia Author Van Ofwegen, Leen P. text Zootaxa 2020 2020-04-16 4764 1 1 131 journal article 22824 10.11646/zootaxa.4764.1.1 55f6b110-0a37-45fe-be1c-34e9a035fe0e 1175-5334 3764923 urn:lsid:zoobank.org:pub:53C5289A-156C-4AF1-B84A-73099A332C05 Litophyton acutum sp. nov. ( Figs. 31 a-b, 32a-b, 33-35) Material examined . Holotype NTM C4107 ; Queensland , Great Barrier Reef , Davies reef, 5-10 m depth, 15 April 1981 , coll. Z. Dinesen ; paratypes : NTM C4108, Queensland , Great Barrier Reef, Rib reef, depth 10-15 m , 26 May 1981 , coll. Z. Dinesen; NTM C1365, Queensland , Great Barrier Reef, Sanctuary reef, 13 November 1980 ; coll. P. Alderslade; NTM C3955, Queensland , Great Barrier Reef, Flinders reef, depth - 2 m ; 22 November 1981 , coll. Z. Dinesen; NTM C3961, Queensland , Great Barrier Reef, Dip reef, depth 1-5 m ; 6 February 1981 , coll. Z. Dinesen; NTM C3979, Queensland , Great Barrier Reef, Flinders reef, S.W., depth 5-10 m ; 26 November 1981 , coll. Z. Dinesen; NTM C3996, coll. Z. Dinesen; NTM C4028, Queensland , Great Barrier Reef, Davies reef, depth 1-5 m , 15 April 1981 , coll. Z. Dinesen. Description . The NTM C4107 holotype is 5 cm high and 10 cm wide, the stalk is 2 cm long ( Fig. 31a ). The polyps are grouped in conical catkins, they are up to 0.5 mm wide and high. Polyps . With irregular arrangement of sclerites in points ( Fig. 32a ). Abaxial and lateral point sclerites are unilaterally spinous or foliaceous spindles, the largest present abaxially, up to 0.50 mm long, laterally they are up to 0.25 mm long ( Fig. 33a ). Adaxially there are only tentacles sclerites, small rods, up to 0.10 mm long ( Fig. 33b ). The polyp stalk next to the adaxial tentacles has a few small almost smooth rods ( Fig. 33c ). Supporting bundle not projecting, composed of spindles up to 1 mm long, with simple tubercles and a somewhat spiny distal end ( Fig. 33d ). Surface layer top stalk . Spindles and unilaterally spinose spindles, up to 0.55 mm long, with simple and complex tubercles and long spines ( Fig. 33e ). Surface layer base stalk . Capstans and derivatives of capstans, spindles and unilaterally spinose spindles, with simple and complex tubercles ( Fig. 33 f-g, 34a). The derivations of capstans and unilaterally spinose spindles have very large spines. The spindles are up to 0.50 mm long. Interior stalk . Spindles, up to 1 mm long ( Fig. 34b, c ), with pointed ends and simple and complex tubercles ( Fig. 34d ). The smaller spindles are often branched. Variability . Paratype NTM C3979 ( Fig. 31b ) overall shows more slender internal spindles ( Fig. 35k ). This is probably caused by different sampling position. Both the holotype and this paratype miss the basal part of the stalk. Etymology. From the Latin acutus , acute, sharp, pointed, refers to the interior spindles with pointed ends. Distribution . Queensland : Davies reef, Rib reef, Sanctuary reef, Flinders reef, Dip reef. Remarks . The holotype obviously is lacking the very base of the stalk ( Fig. 31a ). L . acutum sp. nov. , L . obtusum sp. nov. , and L . territoryensis sp. nov. all have unilaterally spinose sclerites with long spines. L . acutum and L . territoryensis with interior of the stalk with many spindles with pointed ends, but the spindles of L . territoryensis have much finer tuberculation. L . obtusum has many interior stalk spindles with blunt ends and less branched small internal stalk spindles.