Eleutherobia splendens (Thomson & Dean, 1931) new record

(Fig. 7 G; 13; Tabs. 1, 2)

Nidalia splendens Thomson & Dean, 1931: 38, Pl. 1, Fig. 7; Pl. 6, Fig. 9; Pl. 25, Fig. 8. Eleutherobia splendens Verseveldt & Bayer, 1988: 40 –41, Figs. 18 a, 33a, 35, 36c.

Material examined. WAM Z23988, two whole specimens, cylindrical, colony 1 unbranched, 45.3 mm tall, attached to a mollusc shell, colony 2 branched with three branches in one plane, 51.6 mm tall, Station SO1/84/055, Lacepede Archipelago, NW Australia, 19.9500°– 19.9833° S, 120.7338°– 120.7350° E, CSIRO FRV "Soela" cruise VI, trawl, depth 297 m, coll. S.M. Slack-Smith, 10 February 1984; WAM Z54996, one whole specimen, unbranched, 31.5 mm tall, Station SO1/84/056, Kimberley, Beagle Bay, NW Australia, 16.9297° S, 122.5411° E, CSIRO FRV "Soela" cruise VI, trawl, depth 301 m, coll. S.M. Slack-Smith, 11 February 1984. NTM C002899, one whole specimen, 19.3338° S, 115. 6836° E, FRV “Soela” cruise 0 184, trawl, depth, 306–308 m, coll. A.J. Bruce, 29 January 1984; NTM C 013059, one whole specimen, Station SS1005 130-015, off Red Bluff, 23.9908° S, 112. 3547° E, RV "Southern Surveyor", beam trawl, depth 411 m, K. Gowlett-Holmes, 8 December 2005.

Description. The colonies are erect, cylindrical, with large bodied anthocodiae up to 4 mm long (Fig. 7 G). The colonies are unbranched or branched in one plane and are up to 51.6 mm tall. Some specimens are attached to a mollusc shell.

In the surface of the polyparium the majority of the sclerites are thorny clubs, up to 0.22 mm long but mainly between 0.08–0.15 mm, with the warts below the head arranged in girdles (Fig. 13 A). There are also a few 8- radiates present. The majority of sclerites of the base are thorny 8-radiates up to about 0.10 mm long, but there are also a few larger sclerites are up to 0.16 mm that are club-shaped (13B). The sclerites of the interior of the polyparium are markedly narrow, needle-like forms, 0.34–0.47 mm long, with girdles of high spines (Fig. 13 C). The sclerites in the interior of the base are spindles up to 0.35 mm long. They are similar to the sclerites in the interior of the polyparium, but are slightly shorter and wider (Fig. 13 D).

The tentacles contain densely packed stout, flattened rods with a curved end up to 0.45 mm long (Fig. 13 E). The polyp armature is strongly developed. It consists of collaret and point and is formed of slightly curved, spiny spindles around 0.05 mm long (Fig. 13 F).

Colour. The preserved colonies are cream with the distal part of the coenenchymal mounds being sometimes of the same colour, but usually are a distinct pink to red (Fig. 7 G). The tentacles are white. The introvert contains brick-red sclerites.

Habitat. The specimens were sampled from a depth range between 297–411 m along the continental slope utilising otter and beam trawls, but the exact habitat is unknown.

Remarks. Previously this species has only been described from Indonesia and the Philippines (Table 1), making this the first record for Australia. Our specimens agree well with the holotype colony described and figured in the original report of Thomson and Dean, but it is impossible to make any worthwhile comparisons with the rest of their brief description. The notable difference between the characters of our material and the comparable features reported by those authors is the more prickly warting of the sclerites (as was the case with E. somaliensis above). Unfortunately, the redescription did not include illustrations of the polyp sclerites, so we asked Dr Leen van Ofwegen to make a comparison using Verseveldt & Bayer’s microscopic slides of the holotype sclerites of E. splendens held in the Naturalis Biodiversity Centre, Leiden, and he was able to confirm they are of the same form.