Psolidium laperousazi, O’Loughlin & Ahearn, 2008

O’Loughlin, P. Mark & Ahearn, Cynthia, 2008, Australian species of Psolidium Ludwig (Echinodermata: Holothuroidea: Psolidae), Memoirs of Museum Victoria 65, pp. 1-22 : 15

publication ID	https://doi.org/ 10.24199/j.mmv.2008.65.2
DOI	https://doi.org/10.5281/zenodo.8070636
persistent identifier	https://treatment.plazi.org/id/03FC87C9-5616-FFAC-A2B2-FD75FB91F580
treatment provided by	Felipe
scientific name	Psolidium laperousazi
status	sp. nov.

Treatment

Psolidium laperousazi View in CoL sp. nov.

Table 1 View Table 1 , Figures 1c View Figure 1 , 2f View Figure 2 , 6b–c View Figure 6

Material examined. Holotype: SE Tasmania, D’Entrecasteaux Channel , Tinderbox, E of boat ramp, 1.5–3 m, K. L. Gowlett-Holmes, 14 Jul 1991, SAM K2172 View Materials .

Paratypes: type locality and date, K2339 (2); South Australia, Kangaroo I, b/wn Western River Cove and Snug Cove, W side, 8–10 m, K. L. Gowlett-Holmes, 24 Feb 2003, K2179 (1, live colour photo SAM PK0253 View Materials ) .

Description. Psolidium species up to 27 mm long (preserved); body height low to moderately high; dorsal and lateral scales thick, embedded in thick integument, imbricating, up to 1.5 mm wide; dorsal and lateral tube feet conspicuous, abundant.

Sole: peripheral band of tube feet, 3-4 wide, not always continuous anteriorly and posteriorly, lacking series of distinctly separate outer small tube feet; regular, close series of mid-ventral radial tube feet, 2 wide.

Dorsal and lateral ossicles: multi-layered perforated ossicles (scales), thick, irregular form; deeply cupped crosses and more abundant partially and fully closed cups, 40-72 μ m, typical size range 56-64 μ m long, cup rim densely, finely spinous; small to large buttons, up to 12 perforations, thick, smooth, irregular form, up to 264 μ m long, intergrade with multi-layered ossicles.

Ventral ossicles: predominantly large single-layered perforated plates, up to 20 perforations, rarely up to 42 perforations in larger specimens, variable thickening, irregularly round to elongate, smooth, irregular margin, up to 368 μ m long; perforated plates with variable surface and peripheral knobs rare; perforated plates with 4 perforations rare; moderately deep to deeply cupped crosses and more abundant partially and fully closed cups, 48 – 64 μ m long, typical size range 48–56 μ m long, cup rim bluntly spinous.

Tentacle ossicles include rosettes, irregularly oval, densely branched, up to 80 μ m long in larger specimens.

Colour. Live: dark pink dorsally. Preserved: pale brown to cream dorsally and ventrally; small, discrete, dark brown spots may be present on the sole.

Distribution. SE Tasmania (D’Entrecasteaux Channel) to South Australia (Kangaroo I); 1– 10 m.

Etymology. Named for Thierry Laperousaz (Collection Manager, Marine Invertebrates, South Australian Museum), with gratitude for his prompt and gracious assistance with loans.

Remarks. The distinguishing characteristics of Psolidium laperousazi sp. nov. are the embedding of the dorsal and lateral scales in thick integument, the abundant and conspicuous tube feet, the predominance of cups over cupped crosses dorsally and ventrally, large rosettes in the tentacles, and the presence of dark spots on the sole.