Sinularia mesophotica, Benayahu, Yehuda, McFadden, Catherine S., Shoham, Erez & Ofwegen, Leen P. van, 2017

Benayahu, Yehuda, McFadden, Catherine S., Shoham, Erez & Ofwegen, Leen P. van, 2017, Search for mesophotic octocorals (Cnidaria, Anthozoa) and their phylogeny. II. A new zooxanthellate species from Eilat, northern Red Sea, ZooKeys 676, pp. 1-12 : 1-2

Sinularia mesophotica sp. n. Figs 1, 2, 3, 4

Type material examined.

Holotype: ZMTAU Co 37425, Israel, northern Red Sea, Gulf of Aqaba, Eilat, Dekel Beach (29°32'2.49"N, 34°57'44.56"E), 62 m, 31 May 2016, coll. M. Weis; three paratypes: ZMTAU Co 37492 same collection details.

Diagnosis.

The holotype is part of an encrusting colony with a thin, funnel-shaped polypary, also featuring a curly margin (Fig. 1A). In a side-view its maximum dimensions are 5 × 2.5 cm. Polyps with tentacle rods and collaret sclerites (Fig. 2 A–C). Tentacle rods up to 0.10 mm long (Fig. 2A). Collaret consists of almost straight spindles, up to 0.20 mm long (Fig. 2B), and shorter bent ones, up to 0.14 mm long (Fig. 2C). Surface layer of the polypary with clubs (Fig. 2D), some featuring a central wart, while in others it is less discernible, or even absent. Clubs vary from 0.10 mm long to 0.25 mm long, and a few with poorly developed heads attain 0.27 mm (Fig. 2E). Surface layer of the colony base contains clubs up to 0.22 mm; some similar to those of polypary, and others have wide heads (Fig. 3A). Polypary and base interior bear spindles, some branched, up to 3.2 mm long (Fig. 3B), with well-spaced simple tubercles (Fig. 3C).

Color.

The ethanol-preserved holotype is beige.

Etymology.

The new species name reflects its mesophotic habitat.

Living features.

Colonies grow as dense patches over reefal-calcareous substrate. Their polypary is flat and horizontally oriented (Fig. 4A) or funnel-shaped (Fig. 4B), with upper part dark-brown, due to dense zooxanthellae as verified by light microscopy, and lower part brighter, almost white. The flexibility and softness of the living colonies was recognized by their movement in the water currents generated by the ROV arm.

Variability.

ZMTAU Co 37492 comprises three paratypes, each of them represented by fragments of colonies (Fig. 1B). Their general morphology and sclerites are identical to those of the holotype ZMTAU Co 37425.