Litophyton rowleyensis Van 2020, sp. nov.
Creators: name: Van Ofwegen, Leen P.
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Cnidaria
Anthozoa
Alcyonacea
Nephtheidae
Litophyton
Litophyton rowleyensis

description: Litophyton rowleyensis sp. nov.
(Figs. 21 a-e, 13b, g, 22-25)
Material examined. Holotype NTM C10780, Western Australia, Rowley Shoals, Clerke reef, depth 5-10 m, 18 July 1987, coll. J. Hooper; paratypes: NTM C5804, two specimens, same data as holotype; NTM C5807, two specimens, Western Australia, Rowley Shoals, Clerke reef, collected in a lagoon, depth 10 m, 18 July 1987, coll. J. Hooper; NTM C10722, North-Western Australia, July 1987, coll. P. Alderslade; NTM C10737; same data as holotype; NTM C10769, Western Australia, Rowley Shoals.
Description. The holotype NTM C10780 is 4.5 cm high and 8 cm wide, the stalk is 2 cm high (Fig. 21a). The polyps are up to 0.6 mm wide and 0.75 mm high, and are grouped in long catkins.
Polyps. With irregular arrangement of sclerites in eight points (Fig. 13g). Abaxial and lateral point sclerites are spindles with simple tubercles and spiny distal part, largest present abaxially, up to 0.45 mm long (Fig. 22a), towards the adaxial points they become smaller (Fig. 22b). Tentacles with curved scales up to 0.10 mm long (Fig. 22c). Adaxial side of the polyp stalk with straight rods up to 0.15 mm long (Fig. 22e), and platelets up to 0.05 mm long (Fig. 22d). Supporting bundle composed of one or two spindles up to 2.50 mm long, with simple tubercles and a spiny or sometimes smooth tip projecting for a maximum distance of 0.80 mm (Fig. 22f). Many polyp sclerites have an optically black inner core.
Surface layer top stalk. Spindles and unilaterally spinose spindles, up to 1.50 mm long, with simple tubercles (Fig. 22 g-h).
Surface layer base stalk. Capstans, derivatives of capstans, spindles, and unilaterally spinose spindles, with simple tubercles (Fig. 22 i-j). The spindles are up to 1.50 mm long.
Interior stalk. Spindles with pointed ends (Fig. 22 k-l), up to 1.50 mm long, with simple tubercles (Fig. 22m).
Etymology. Named after the type locality.
Distribution. Western Australia: Rowley Shoals.
Remarks. The specimens of Litophyton rowleyensis show a considerable variation concerning colony shape (Fig. 21 a-e) and sclerites (Figs. 22-25). One of the paratypes of NTM C5807 (Fig. 21d) and NTM C10722 (Fig. 21c) lack the basal part of the stalk and show shorter internal spindles, only up to 1.00 mm long (Fig. 24e), with complex tubercles, and less spiny surface stalk sclerites (Fig. 23 j-k). The other paratype of NTM C5807 (Fig. 21e) shows the longest internal stalk spindles, up to 2.00 mm long (Fig. 25j). One of the paratypes of NTM C5804 (Fig. 21b) has many rather smooth internal stalk sclerites (Fig. 24 a-c).
The paratype of NTM C5807 having the largest internal stalk sclerites (Fig. 25j) suggests this is the specimen with most of the stalk intact as in general the internal stalk sclerites become larger towards the base of the stalk (see material and methods). Apparently also the holotype lacks a bit of the base which is sometimes difficult to observe as with collecting a broken stalk tends to close fast (my field observations while collecting nephtheids).
The other Litophyton species with projecting supporting bundle spindles with a smooth tip, L. pseudorowleyensis sp. nov., has the supporting bundle projecting for a maximum distance of only 0.30 mm. Furthermore, it has far less sclerites in the polyp stalk.
description: Published as part of Van Ofwegen, Leen P., 2020, The genus Litophyton Forskål, 1775 (Octocorallia: Alcyonacea: Nephtheidae) from Australia, pp. 1-131 in Zootaxa 4764 (1) on page 31, DOI: 10.11646/zootaxa.4764.1.1, http://zenodo.org/record/3764923