Xenia multispiculata Kükenthal, 1909

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 : 219-220

Xenia multispiculata Kükenthal, 1909

Fig. 10

Xenia multispiculata Kükenthal, 1909: 47

Material. Syntype: ZMB 6920 , South Pacific Ocean , Tonga Island, Viti, collected by Dr. H. Merton.

Description. The holotype is 28 mm high; its stalk is 16–20 mm long, 10 mm wide at its base and 15 mm wide at the uppermost part. The polyp body is up to 10 mm long, and the tentacles up to 9 mm long, featuring two irregular rows of pinnules on each side. The pinnules are short and stout, up to 0.8 mm long and 0.2 mm wide, 21– 29 in the outermost row with a gap of one pinnule-width space between adjacent ones.

Sclerites are ellipsoid platelets, measuring 0.011 –0.018 X 0.019 –0.025 mm in diameter ( Fig. 10a, n =20). They are comprised of calcite rods, which are uniform in width and assembled randomly within the sclerite center ( Fig. 10b, c ). The sclerite surface is granular and occasionally fractured. The ethanol-preserved holotype is beige in color.

Remarks. The re-description of X. multispiculata corresponds to the original description.

Similar species and conclusion. X. multispiculata is the only Xenia species among those examined in this study to display two rows of pinnules. It shares sclerite microstructure with X. novaebritanniae Ashworth, 1900 , X. bauiana and X. blumi but differs in pinnule arrangement and thus should be considered as a separate species.

Distribution. South Pacific Ocean: Tonga Island.

Figures

FIGURE 10. Scanning electron micrographs of polyp sclerites of Xenia multispiculata Schenk, 1896 Syntype (ZMB 6920). a. Ellipsoid platelets, some fractured; b. Fractured sclerites; c. Fractured sclerites composed of a latticework matrix of calcite rods, dendritic and sinuous, radially arranged in the peripheral region. Scale bar at a and b 0.010 mm, at c 0.002 mm.