Xenia lepida Verseveldt, 1971

Halász, Anna, Mcfadden, Catherine S., Toonen, Robert & Benayahu, Yehuda, 2019, Re-description of type material of Xenia Lamarck, 1816 (Octocorallia: Xeniidae), Zootaxa 4652 (2), pp. 201-239 : 216

Xenia lepida Verseveldt, 1971

Xenia lepida Verseveldt, 1971: 65 –67

Xenia lepida ; Janes 2013; Janes et al. 2014; McFadden et al. 2014b

Material. Holotype: RMNH Coel no. 6703, Indian Ocean , Madagascar, Nosy Bé, Pointe lokombe, 10 m, 18 July 1967, coll. A. G. Humes ; Paratype: RMNH Coel. no. 6704, same collection data .

Description. The holotype is 40 mm high; its stalk splits three times, 15 mm above the colony attachment to the substratum. The first branch is 14 mm long, the second is 24 mm long and splits at its distal part, the third is 22 mm long and splits four times. They are all 5 mm wide at their base and at their uppermost part. The polyp body is up to 16 mm long, and the tentacles up to 12 mm long, featuring three rows of pinnules on each side, with approximately 28–34 pinnules in the outermost row. Most of the polyps are extended, and the arrangement of the pinnules is irregular, with the total number of pinnules reaching 40 and more. The pinnules are relatively slender, up to 0.24 mm long and 0.16 mm wide, with spacing of half a pinnule-width up to 2 pinnule-widths between adjacent pinnules. Sclerites are not present in any part of the colony. The ethanol-preserved holotype is light beige.

The paratype is 47 mm high; its stalk is 34 mm long, 5 mm wide at its base, and 5 mm wide at its uppermost part. The polyp body is up to 6 mm long, and the tentacles up to 7 mm long, featuring three rows of pinnules on each side. The pinnules are relatively slender, up to 0.50 mm long and 0.16 mm wide, 24–32 in the outermost row with spacing of no gap up to half a pinnule-width between adjacent pinnules. As in the holotype, no sclerites were found in the paratype. The ethanol-preserved paratype is light beige.

Remarks. The current findings correspond to the original description of X. lepida , except for the latter referring to sclerites 0.009 mm in diameter in the stalk and 0.015 mm long in the polyps, visible only under a polarizing microscope. The two measurements most probably refer to symbiotic algae (zooxanthellae), which confused the author, rather than to the sclerites. In the current study no sclerites were found in any part of the colony.

Similar species and conclusion. Both X. sansibariana and X. lepida feature a similar number of pinnules in the outermost row and lack sclerites in all parts of the colony. They differ in the number of pinnule rows (4 vs. 3, respectively) and thus should be considered as separate. The original description of X. lepida by Verseveldt (1971) mentioned its similarity to X. distorta Tixier-Durivault, 1966 . For the purpose of the current study, inquiries made to the Muséum National d’Histoire Naturelle, Paris ( MNHN) indicated that the type most probably got lost and therefore regrettably could not be compared to X. lepida .

Distribution. Indian Ocean: Madagascar, Indonesia: Lembeh Strait.