Latissimia opalia Ekins, Benayahu & McFadden 2022, sp. nov.
Creators: name: Benayahu, Yehuda
name: Ekins, Merrick
name: Van Ofwegen, Leen P.
name: Samimi-Namin, Kaveh
name: Mcfadden, Catherine S.
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Cnidaria
Anthozoa
Alcyonacea
Xeniidae
Latissimia
Latissimia opalia

description: Latissimia opalia Ekins, Benayahu & McFadden, sp. nov.
Figures 1, 8–10
http://zoobank/ urn:lsid:zoobank.org:act: 7CA36992-98F8-478D-BE5A-A2318722193D
Material. Australia. Holotype: QM G339447, Shelly Beach, Caloundra, Queensland (26.79972° S, 153.150278° E), Intertidal pools of beach rock, 0.1–1 m, 23 February 2021, coll. M. Ekins; Paratypes: QM G339756 - QM G339762 and QM G339448 - QM G339450, all same details; QM G333523, same location as the holotype, 4 June 2013, coll. M. Ekins & J. Johnson; QM G317135, same location as the holotype, 30 June 2000, coll. S. Cook, & D.
Edson; QM G317204, Dunwich, North Stradbroke Island, Queensland, Australia (27.494167° S, 153.400000° E), 0.1–1 m, 23 September 2000, coll. J. Hooper, S. Cook, J. Kennedy, S. List-Armitage, D. Edson and G. Wörheide.
Description. The holotype measures 30 x 23 mm and is 8 mm in height (Fig. 8A), featuring polyps attached to an encrusting 3 mm thick spreading membrane. The polyps are up to 11 mm in length with the majority being around this size, and a few contracted ones of only 2 mm in length. The lower part of the polyps below the tentacles is 1–1.5 mm in width. The expanded tentacles are approximately 1.5 mm long with two rows of 24–30 pinnules on either side of the tentacle.
The sclerites of the holotype are ellipsoid platelets, a few with a waist-like median narrowing, either on one or both sides of the sclerite (Fig. 9A). Under an incident light microscope they are opalescent blue and abundant throughout the colony, measuring 0.008 –0.013 x 0.016 –0.019 mm in diameter. The sclerites are composed of calcite rods whose tips provide a uniform granular appearance to the sclerite surface (Fig. 9B). Some sclerites tend to fracture during the dehydration process necessary for SEM.
Color. The ethanol-preserved holotype is cream/light orange.
Etymology. The species name, opalia, is derived from the Latin opalus, referring to the opal-blue color of the live colonies.
Variation. The morphological features of the paratype colonies resemble the holotype, except in size (Fig. 8 B–H).
Remarks. L. opalia is characterized by large non-retractile blue polyps when alive (Fig. 10) and a relatively thick spreading membrane providing a fleshy appearance. Another xeniid, Sympodium caeruleum Ehrenberg, 1834, similarly has encrusting colonies with a bluish tinge when alive (Benayahu et al. 2021). However, it differs from L. opalia by having a much thinner and more delicate spreading membrane and fully retractile polyps. All of the sequenced samples of L. opalia were assigned to MOTU72, thus indicating that the geographic distribution of L. opalia includes the Queensland (eastern Australia) intertidal rock platforms and mudflats (Fig. 1).
Living features. The live colonies are blue/brown in color (Fig. 10 A–B). Higher magnification of the polyps and tentacles clearly demonstrates the characteristic blue coloration of the sclerites (Fig. 10 C–F). At low tide the polyps in direct sunlight contract such that their sclerites form an almost complete barrier blocking out the sunlight and giving the colonies their blue color, with the creamy-brown color of the underlying tissue apparent between the sclerites.
Distribution. South-eastern Queensland and northern New South Wales, Australia (Fig. 1).
description: Published as part of Benayahu, Yehuda, Ekins, Merrick, Van Ofwegen, Leen P., Samimi-Namin, Kaveh & Mcfadden, Catherine S., 2022, On some encrusting Xeniidae (Octocorallia): Re-examination of the type material of Sansibia flava (May, 1898) and a description of new taxa, pp. 421-444 in Zootaxa 5093 (4) on pages 430-433, DOI: 10.11646/zootaxa.5093.4.3, http://zenodo.org/record/5912731