Ovabunda macrospiculata (Gohar, 1940)

Halasz, Anna, McFadden, Catherine S., Aharonovich, Dafna, Toonen, Robert & Benayahu, Yehuda, 2014, A revision of the octocoral genus Ovabunda Alderslade, 2001 (Anthozoa, Octocorallia, Xeniidae), ZooKeys 373, pp. 1-41 : 28-31

Ovabunda macrospiculata (Gohar, 1940) Figs 17 ,18 ,19

Xenia macrospiculata Gohar, 1940: 96-98; Benayahu 1990 table 1 listed only; Reinicke 1997: 42, plates 1-3, 29.

Ovabunda macrospiculata ; Alderslade 2001: 51, figs 29-30.

Xenia macrospiculata Not; Verseveldt 1971: 64-65, fig. 39.

Material.

Neotype: ZMTAU Co 25635, northern Red Sea, Gulf of Suez, Shag Rock (27°47'1.48"N, 33°59'23.17"E), <5m, 11 July 1986, coll. Y. Benayahu. Paratypes: ZMTAU Co 35789 (field number A69) northern Red Sea, Gulf of Aqaba, Underwa ter Restaurant (29°32'49.43N, 34°57'14.51"E), 5 m, 3 May 2010, coll. A. Halász; ZMTAU Co 35790 (field number A70) northern Red Sea, Gulf of Aqaba, The Interuniversity Institute of Marine Sciences in Eilat (IUI) (29°30'6.54"N, 34°55'4.44"E), 22 m, 4 May 2010, coll. A. Halász; ZMTAU Co 35791 (field number A72), collection details as above, 9 m.

Description.

The neotype is 20 mm high. Its stalk is 10 mm wide at its base, splitting into three branches, 7, 5 and 5 mm long; 5, 4 and 4 mm wide at the base and 10, 6 and 7 mm wide at the uppermost part, respectively. Polyp’s body reaches up to 2 mm and tentacles up to 5 mm, bearing three, occasionally two, rows of pinnules. The pinnules are 1 mm long and 0.2 mm wide, with less than a pinnule-width space between them, and there are 15-17 pinnules in the outermost row on each side of the tentacle. The sclerites are Ovabunda -type, both regular and pear-shaped, measuring 0.015-0.025 × 0.023-0.041 mm (n = 34, Fig. 17a, b ). Occasionally two sclerites are fused, reaching 0.041 mm in maximal diameter ( Fig. 17c ).

The other specimens (ZMTAU Co 35789, 35790, 35791) are of similar size to the neotype; all with three rows of pinnules aligned on both sides of the tentacles, and 14-18, 14-17 and 14-17 pinnules in the outermost row, respectively. Their sclerites are of the Ovabunda -type and vary in shapes from regular to irregular, pear-shaped or fused. Their size ranges through 0.016-0.025 × 0.023-0.043 mm; 0.014-0.03 × 0.019-0.043 mm ( Fig. 18 ) and 0.015-0.027 × 0.022-0.046 mm ( Fig. 19 ) in diameter, respectively (n = 21 for each colony).

Remarks.

Xenia macrospiculata was originally described by Gohar (1940) from Ghardaqa, Egyptian Red Sea, as having pulsating tentacles, bearing three, occasionally two, rows of pinnules, with 12-16 pinnules in the outermost row (and 10-14 pinnules on the middle row, 0-10 on the oral one). That study did not indicate the museum in which the type was deposited. The last author of the current study searched in the museums listed in the Methods and found no trace of it; over time this type was probably lost. The designation of a neotype in this revision is thus necessary. The purpose of the designation is to clarify the species’ taxonomic status and its assignment to Ovabunda . Although the sclerites were described quite accurately in the original description (0.024-0.036 mm in diameter, and "spicules fused in pairs"), SEM micrographs of the sclerites are essential as in the other species of the revision.

The neotype was collected in proximity to the collection site of the original specimen collected by Gohar. The neotype is located at ZMTAU, and available upon request for future examination.

Ovabunda macrospiculata was also described by Verseveldt (1971: 64-65, fig. 39) from Nosy Be, Madagascar, referring to three and sometimes four rows of pinnules with 12-16 pinnules in the outermost row, and sclerites 0.020-0.042 mm in maximal diameter. Examination of RMNH Coel. 6702 from that study revealed that its tentacles have mostly four, rarely three rows of pinnules, and 14-16 pinnules in the outermost row (Reinicke 2013, pers. comm.). During our study the sclerites were examined and they are indeed Ovabunda -type, measuring up to 0.043 mm in maximum diameter, while fused sclerites are 0.055 mm in diameter. Based on the number of rows of pinnules and the number of pinnules at the outermost row, we conclude that it does not agree with Ovabunda macrospiculata .

Similar species.

Ovabunda macrospiculata is most similar to Ovabunda ainex . Although they both have three rows of pinnules, the numbers of pinnules in the outermost row ranges from 14-18 in Ovabunda macrospiculata compared to 15-20 in Ovabunda ainex . The major difference between them is that Ovabunda macrospiculata presents pulsating polyps in live colonies and Ovabunda ainex does not.

Distribution.

Red Sea: Gulf of Aqaba, southern tip of Sinai Peninsula.

Figures

Figure 17. Scanning electron micrographs of polyp sclerites of Ovabunda macrospiculata (Gohar, 1940) neotype (ZMTAU Co 25635). a Pear-shape sclerite b Regular sclerites c Fused sclerite. Scale bar 10 µm.

Figure 18. Scanning electron micrographs of polyp sclerites of Ovabunda macrospiculata (Gohar, 1940) paratype (ZMTAU Co 35790). a Regular sclerites b Irregular sclerite c Fused sclerites d Pear-shaped sclerite. Scale bar 10 µm.

Figure 19. Scanning electron micrographs of polyp sclerites of Ovabunda macrospiculata (Gohar, 1940) paratype (ZMTAU Co 35791). a Regular sclerite b Irregular sclerites c Fused sclerites. Arrows indicate surface dents. Scale bar 10 µm.