Xenia ternatana Schenk 1896
Creators: name: Halász, Anna
name: Mcfadden, Catherine S.
name: Toonen, Robert
name: Benayahu, Yehuda
Publisher: name: Zenodo
Year: 2019
Subjects: Biodiversity
Taxonomy
Animalia
Cnidaria
Anthozoa
Alcyonacea
Xeniidae
Xenia
Xenia ternatana

description: Xenia ternatana Schenk, 1896
Fig. 14
Xenia ternatana Schenk, 1896: 64, plate 3, Fig. 16
Xenia ternatana; Kükenthal 1902: 649; Tixier-Durivault 1966: 359; Verseveldt & Cohen 1971: 62; Benayahu 1990: 118, table 1, listed only; Reinicke 1997: 35–36; Janes 2013; Janes et al. 2014; McFadden et al. 2014a.
Material. Holotype and paratype: SMF 43, Indonesia, Ternate Island, 1894, coll. W. Kükenthal.
Description. The holotype is the larger colony under SMF 43, 25 mm high; its stalk is 18 mm long, 10 mm wide at its base and 15 mm at its uppermost part. The syntype is 23 mm high; its stalk is 12 mm long, 15 mm wide at its base, 22 mm wide at its uppermost part. The polyp body is up to 3.5–5 mm long, and the tentacles up to 3–3.5 mm long, featuring three rows of pinnules on each side. The pinnules are relatively slender, up to 0.5 mm long and 0.2 mm wide, 15–23 in the outermost row with no gap between adjacent ones.
Sclerites are present in all parts of the colony, more densely arranged on the aboral side of the tentacles and less so in the pinnules. They are ellipsoid platelets, measuring 0.008 –0.015 X 0.017 –0.021 mm in diameter (Fig. 14, n=20). Their surface is granular due to the dendritic rods that comprise the sclerite (Fig. 14c). Some sclerites feature a distinct longitudinal crest (Fig. 14c). The ethanol-preserved holotype is dark gray in color.
Remarks. The original description of X. ternatana by Schenk (1896) indicated two rows of pinnules and 18– 22 pinnules in each row compared to the three rows and 15–23 pinnules in the outermost row as revealed in the present study. The current examination demonstrated that some of the sclerites possess a central crest, resembling those of Yamazatum Benayahu, 2010. As already indicated, it is suggested that the presence of a crest on the sclerite surface is diagnostic and important for xeniid species identification. Colonies of X. ternatana from various locations in the Red Sea (e.g., Kükenthal 1913; Verseveldt & Cohen 1971; Benayahu 1990) should be re-examined in order to verify the microstructure of their sclerites. Reinicke (1997) examined the type of X. ternatana and other material from the Red Sea, but repeated the original description and not his findings concerning the type; therefore, his material should also be re-examined. In McFadden et al. (2014a) a specimen collected from Indonesia bearing two rows of pinnules was identified as X. ternatana, which does not correspond to the current re-description of the type.
Similar species and conclusion. X. viridis, X. blumi, X. umbellata Lamarck, 1816 and X. ternatana share a similar pinnule arrangement, but differ in their sclerite microstructure (Figs 15, 3, 16 and 14, respectively), and therefore it is concluded that they should be considered as separate species.
Distribution. Indonesia: Ternate Island.
description: Published as part of Halász, Anna, Mcfadden, Catherine S., Toonen, Robert & Benayahu, Yehuda, 2019, Re-description of type material of Xenia Lamarck, 1816 (Octocorallia: Xeniidae), pp. 201-239 in Zootaxa 4652 (2) on page 224, DOI: 10.11646/zootaxa.4652.2.1, http://zenodo.org/record/3363653