Litophyton rowleyensis, Van, 2020

Van Ofwegen, Leen P., 2020, The genus Litophyton Forskål, 1775 (Octocorallia: Alcyonacea: Nephtheidae) from Australia, Zootaxa 4764 (1), pp. 1-131 : 31

publication ID	https://doi.org/ 10.11646/zootaxa.4764.1.1
publication LSID	urn:lsid:zoobank.org:pub:53C5289A-156C-4AF1-B84A-73099A332C05
DOI	https://doi.org/10.5281/zenodo.3803570
persistent identifier	https://treatment.plazi.org/id/03BCB717-233F-FFCE-FF35-85F4FE7BFA75
treatment provided by	Carolina
scientific name	Litophyton rowleyensis
status	sp. nov.

Treatment

Litophyton rowleyensis View in CoL sp. nov.

( Figs. 21 View FIGURE 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 View FIGURE 21 ). 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 View FIGURE 13 ). 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 View FIGURE 22 ), towards the adaxial points they become smaller ( Fig. 22b View FIGURE 22 ). Tentacles with curved scales up to 0.10 mm long ( Fig. 22c View FIGURE 22 ). Adaxial side of the polyp stalk with straight rods up to 0.15 mm long ( Fig. 22e View FIGURE 22 ), and platelets up to 0.05 mm long ( Fig. 22d View FIGURE 22 ). 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 View FIGURE 22 ). 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 View FIGURE 22 g-h).

Surface layer base stalk. Capstans, derivatives of capstans, spindles, and unilaterally spinose spindles, with simple tubercles ( Fig. 22 View FIGURE 22 i-j). The spindles are up to 1.50 mm long.

Interior stalk. Spindles with pointed ends ( Fig. 22 View FIGURE 22 k-l), up to 1.50 mm long, with simple tubercles ( Fig. 22m View FIGURE 22 ).

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 View FIGURE 21 a-e) and sclerites ( Figs. 22-25 View FIGURE 22 View FIGURE 23 View FIGURE 24 View FIGURE 25 ). One of the paratypes of NTM C5807 ( Fig. 21d View FIGURE 21 ) and NTM C10722 ( Fig. 21c View FIGURE 21 ) lack the basal part of the stalk and show shorter internal spindles, only up to 1.00 mm long ( Fig. 24e View FIGURE 24 ), with complex tubercles, and less spiny surface stalk sclerites ( Fig. 23 View FIGURE 23 j-k). The other paratype of NTM C5807 ( Fig. 21e View FIGURE 21 ) shows the longest internal stalk spindles, up to 2.00 mm long ( Fig. 25j View FIGURE 25 ). One of the paratypes of NTM C5804 ( Fig. 21b View FIGURE 21 ) has many rather smooth internal stalk sclerites ( Fig. 24 View FIGURE 24 a-c).

The paratype of NTM C5807 having the largest internal stalk sclerites ( Fig. 25j View FIGURE 25 ) 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 View in CoL 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.