Eleutherobia australiensis, Bryce, Monika, Poliseno, Angelo, Alderslade, Philip & Vargas, Sergio, 2015

Bryce, Monika, Poliseno, Angelo, Alderslade, Philip & Vargas, Sergio, 2015, Digitate and capitate soft corals (Cnidaria: Octocorallia: Alcyoniidae) from Western Australia with reports on new species and new Australian geographical records, Zootaxa 3963 (2), pp. 160-200 : 169-171

publication ID	https://doi.org/ 10.11646/zootaxa.3963.2.2
publication LSID	lsid:zoobank.org:pub:86A305B7-2B9C-403E-8FC0-3420EFB13F52
DOI	https://doi.org/10.5281/zenodo.5680252
persistent identifier	https://treatment.plazi.org/id/03B687F9-A456-FFED-17DB-50DF4E17F968
treatment provided by	Plazi
scientific name	Eleutherobia australiensis
status	sp. nov.

Treatment

Eleutherobia australiensis View in CoL sp. nov.

( Figs. 7A–C View FIGURE 7. A – C , 8 View FIGURE 8 , 9 View FIGURE 9 ; Tabs. 1, 2)

Material examined. Holotype: WAM Z31488, one sectioned colony, Station PF06/S1-200/R 2, 190 km NW of Dampier, Pluto Gas Field, NW Australia, 19.9352°– 19.9308°S, 115.3261°– 115.3288° E, epibenthic sled, depth, 200 m, coll. B.F. Cohen, 8 December 2005. Paratype: WAM Z66778, one whole specimen, same data as holotype.

Description. The holotype is a tapering digitiform colony, with a small lobe ( Fig. 7A–C View FIGURE 7. A – C ) and it is attached to a piece of hard coral skeleton. It is 50 mm tall, 4 mm in diameter at the apex and 10 mm in diameter across the holdfast. The polyp-free basal portion is very short and occupies only 10 % of the total colony length ( Fig. 7A View FIGURE 7. A – C ). Polyps are large, monomorphic, evenly distributed over the polyparium and are completely retracted leaving distinct, rounded coenenchymal mounds on the surface.

In the surface of the polyparium the majority of the sclerites are spindles, 0.10–0.35 mm long, with pointed ends, and ovals 0.08–0.22 mm long ( Fig. 8 View FIGURE 8 A). Sclerites of the coenenchymal mounds are small, spindle-like bodies 0.10–0.15 mm long ( Fig. 8 View FIGURE 8 B). The sclerites of the interior coenenchyme of the polyparium are few, being, thin spindles up to 0.4 mm long ( Fig. 8 View FIGURE 8 C).

The stalk surface is densely spiculated mainly with warty ovals, short, plump spindles 0.10–0.30 mm long with tapering ends and some irregular bodies ( Fig. 9 View FIGURE 9 A). The sclerites of the interior coenenchyme of the stalk are thin spindles, 0.10–0.35 mm long, plump spindles, 0.10–0.25 mm long, with the ends tapering to a point and a few irregular, somewhat triangular forms of similar size ( Fig. 9 View FIGURE 9 B). All of the above sclerites have high, prickly, complex warts

The armature of the polyps consists of a collaret eight to ten rows deep and points of six to eight pairs of curved flattened spindles 0.25–0.45 mm long ( Fig. 8 View FIGURE 8 D). The tentacles contain spikey rods up to 0.07 mm long ( Fig. 8 View FIGURE 8 E; only smaller sclerites up to 0.05 mm are figured due to SEM preparation difficulties). No introvert sclerites are present.

Colour. The preserved colonies are light grey with small orange, rounded coenenchymal mounds. The wider, polyp-free encrusting base is uniformly light grey. The interior coenenchyme is light brown. Surface and internal coenenchymal sclerites are colourless, while the sclerites of the coenenchymal mounds are pale-ochre to reddish.

Etymology. The species is named for being collected in Australia.

Habitat. The specimens were sampled from 200 m along the continental slope utilising an epibenthic sled, but the exact habitat is unknown.

Variability. The paratype is digitiform, with a wide base, and tapering distally towards the rounded apex of the polyparium. It is 45 mm in total length and 3 mm in diameter at the apex. The holdfast is laterally flattened, 15 mm wide and 4 mm thick. The specimen is attached to a piece of hard coral skeleton.

Remarks. The new species is characterised by coenenchymal mounds which are orange because of the coloured sclerites, anthocodial armature of flattened spindles, distinct oval sclerites and long warty spindles in the polyparium surface, and the occurrence of plump spindles with tapered, pointed ends in the lower part of the colony. The ovals and the plump, tapering spindles found in the new species are very like those found in E. dofleini (Kükenthal, 1906) , however, in that species these sclerites occur in both the lower and upper parts of the colony. Also, the shape of the colony is very different (see Verseveldt & Bayer 1988: Fig. 19 View FIGURE 19 a) and the warts on the sclerites are lower and far less prickly.