Litophyton curvum, van Ofwegen, Leen P., 2016

van Ofwegen, Leen P., 2016, The genus Litophyton Forskal, 1775 (Octocorallia, Alcyonacea, Nephtheidae) in the Red Sea and the western Indian Ocean, ZooKeys 567, pp. 1-128 : 10-12

Taxon classification Animalia Alcyonacea Nephtheidae

Litophyton curvum sp. n. Figures 1D, 26, 27, 28, 29, 30, 31, 32

Material examined.

ZMTAU Co 28555 (E167), holotype and seven paratypes, Eritrea, Dahlak Archipelago, Dur Ridgrig, depth 8 m, 15 October 1993, coll. Y. Benayahu; paratypes: ZMTAU Co 25670 1873, Red Sea, South tip Sinai, Shab el Utaf, depth 0-20 m, 11 July 1987, coll. Y. Benayahu; ZMTAU Co 26223, Red Sea, Gulf of Aqaba, 10 km south of Dahab, 24 July 1972, coll. L. Fishelson; ZMTAU Co 26225, Red Sea, South tip Sinai Ras um Sud, 11 April 1972, coll. Y. Benayahu; ZMTAU Co 28549 (E241); Eritrea, Dahlak Archipelago, Sarad, depth 3 m, 17 October 1993, coll. Y. Benayahu; ZMTAU Co 28552 (E261), Red Sea, Dahlak Archipelago, Daliacus, depth 3 m, 18 October 1993, coll. Y. Benayahu; ZMTAU 32929, Eritrea, Dahlak Archipelago, between Nocra Is. and Dahlak Is., southern entrance to the channel, 15°41.36'N, 39°56.08'E, depth 0-5 m, 14 February 2005, coll. Y. Benayahu; ZMTAU Co 32964, Eritrea, Dahlak Archipelago, Shumma Is., 15°32.00'N, 40°00.00'E, depth 8-12 m, 16 February 2005, coll. Y. Benayahu.

Removed from the species.

RMNH 12317, (identified as Nephthea striata by Verseveldt, Red Sea, Gulf of Aqaba, Sharm el Sheikh, depth 30 m, 7 September 1976, coll. Y Benayahu.

Diagnosis.

Litophyton with the internal spindles of the base of the stalk mostly with pointed ends. Polyp stalk with scales. Surface layer of the stalk with straight and curved sclerites.

Description.

The flabby holotype ZMTAU Co 28555 is 5.5 cm long and wide (Figure 26A); the colony is bent to one side.

The polyps are up to about 0.5 mm wide and 0.6 mm high (Figure 27). Supporting bundle not projecting, composed of spindles with simple tubercles, outer side and distal end with larger tubercles (Figure 28A). Length of these spindles is up to 1.0 mm. Polyp body sclerites irregularly arranged, the smallest are present adaxially (Figure 28B); abaxially they merge into the smaller spindles of the supporting bundle and have a thorny outer side (Figure 28C). The tentacle sclerites are small rodlets up to 0.1 mm long (Figure 28D). The polyp stalk has scales up to 0.05 mm long (Figure 28E).

Surface layer top of stalk. Radiates, derivatives of these, spindles and unilaterally spinose spindles (Figure 29 A–B); the latter up to 0.6 mm long.

Surface layer base of stalk. Radiates, derivatives of these, spindles and unilateral spinose spindles (Figures 29C, 30A); the spindles and unilateral spinose spindles are up to 0.5 mm long; many are slightly curved.

Interior base of stalk. Spindles, up to 1.0 mm long, with widely spaced simple tubercles (Figure 30 B–D); some spindles branched.

Etymology.

The Latin “curvum”, curve, curved object or line, refers to the curved spindles from the surface of the stalk.

Distribution.

Red Sea: Gulf of Aqaba, Dahlak Archipelago.

Remarks.

ZMTAU Co 26223, ZMTAU Co 26225 and ZMTAU Co 28552 are slightly different from the holotype. They show less compressed colony shapes (Figure 26D).

To show variation, the sclerites of ZMTAU Co 28552 are also presented (Figures 31-32).

The species can be confused with Litophyton chabrolii (Andouin, 1828), but that species has stiffer colonies, stronger polyp armature, and wider, more regular shaped internal stalk spindles. Litophyton laevis ( Kükenthal, 1913) is also similar to this species, but lacks the curved spindles and unilateral spinose spindles in the surface layer of the base of the stalk. Moreover, both these species do not have the polyp stalk scales present in Litophyton curvum .