Thyone nigra Joshua and Creed, 1915

O’Loughlin, P. Mark, Barmos, Shari & VandenSpiegel, Didier, 2012, The phyllophorid sea cucumbers of southern Australia (Echinodermata: Holothuroidea: Dendrochirotida: Phyllophoridae), Memoirs of Museum Victoria 69, pp. 269-308 : 300-303

Thyone nigra Joshua and Creed, 1915

Figures 5b , 21

Thyone nigra Joshua and Creed, 1915: 20–21 , pl. 3 figs 3a–e, 4.— H. L. Clark, 1946: 401.—A. M. Clark, 1966: 347–348, figs 10b, c.— Rowe, 1982: 462, fig. 10.29a.— Rowe and Gates, 1995: 316.

Material examined. Holotype. South Australia, Dr. Verco, SAM K1376 (specimen and slide).

Other material. Victoria, Westernport Bay, McHaffie Reef , 16 Feb 2008, NMV F151855 (1; photo live) ; Port Phillip Bay, Corio Bay , PPS , Area 26 stn 300–301, 6 m, 16 May 1963, NMV F73807 (2) ; PPS, Corio Bay, Area 27 stn 41, 3 m, 16 Feb 1958, NMV F73808 (1).

Tasmania, Bass Strait, Waterhouse Passage , 40º49'S 147º38'E, rocky shallows, 23 Nov 1982, NMV F97425 (2) ; 26 Feb 1991, NMV F174901 (1).

South Australia, Upper Spencer Gulf, Backy Point , 18 m, Sep 1987, SAM K2561 (1) ; Ward Spit , 9 m, Feb 1986, SAM K1799 (1) ; Eyre Peninsula, Elliston , 33º39'S 134º53'E, rocky shallows, 18 Jan 1991, NMV F97426 (1) ; Point Westall (near Streaky Bay ), 32º55'S 134º04'E, 0 m, 15 Jan 1991, NMV F97427 (1) ; Great Australian Bight, Point Sinclair , 32º06'S 132º59'E, 10 May 1973, NMV F97424 (3).

Western Australia, Busselton , 1 Mar 1962, WAM Z31985 (1) ; Cockburn Sound, Woodman’s Point , 13 Feb 1972, WAM Z31983 (4) ; 1 m, 25 Aug 1971, WAM Z31963 (2) ; Jervoise Groyne , 2 m, 1 Nov 1959, WAM Z31835 (1) ; Perth, Ocean Reef boat harbour, 10–14 m, May 1990, WAM Z31981 (1).

Diagnosis. Thyone species up to 35 mm long, up to 11 mm diameter (preserved; NMV F151855 specimen 42 mm long live, 17 mm long preserved), body fusiform, tapered to rounded end orally and anally, sometimes oral and anal ends upturned, thick firm body wall; external anal scales not detected; 10 tentacles, 8 large, 2 ventral small; complete cover of spaced tube feet, paired to multiple series of contiguous tube feet radially, scattered inter-radially, diameter about 0.2 mm; tubular composite calcareous ring, posterior ends of composite plates not joined; radials tapered anteriorly with terminal split, deep posterior division about half composite plate length, paired composite ends narrow, free; inter-radials tapered to anterior point, truncate posteriorly, inter-radial composite plate extending about half the length of the radial plate; stone canal attached to side of calcareous ring, split pea madreporite form; single polian vesicle, elongate, tubular; longitudinal muscles cylindrical; gonad tubules unbranched.

Mid-body wall ossicles tables, discs irregularly oval to rounded rectangular with 4 central large perforations, 4 and up to about 26 outer smaller perforations, small table discs typically 80 µ m long, large table discs up to 120 µ m long, tables inter-grade with endplate support tables with narrow curved discs up to 136 µ m long, table spires with 2 pillars, single cross-bar, spinous distally, spire height up to 32 µ m; tube feet with endplates, endplate support tables (above); endplates with irregular perforations, small centrally, large marginally, up to about 160 µ m diameter; peri-oral body wall ossicles tables, rosettes, tables irregularly oval to elongate, 2 pillars, up to 30 disc perforations, discs up to 90 µ m long, rosettes oval to bi-lobed, up to 50 µ m long; tentacles rarely with rods, perforated ends, predominantly straight and curved more than bracket-shaped, up to 72 µ m long, rods inter-grade with rosettes, rosettes abundant, many linear.

Colour (preserved). Body white with dark brown flecking/ blotching, darker to black orally and anally, tube feet white with rare dark brown flecks; tentacle trunks brown with white spots (clusters of rosettes), tentacle branches dark grey.

Type locality. South Australia (precise collecting locality not recorded by collector Dr J. C. Verco) .

Distribution. Southern Australia, east to Westernport Bay, north Tasmania (Bass Strait), west to Perth (Western Australia), rocky shallows and offshore sediments, 0– 18 m.

Remarks. Thyone nigra Joshua and Creed, 1915 is distinguished from other southern Australia Thyone species in the key (above).

Figures

Figure 5. Photos of live specimens. a juvenile of Lipotrapeza vestiens (Joshua, 1914) from Eagles Nest, coast of Victoria, with body wall tables and ventral tube feet only (3 mm long; photo by Leon Altoff); b, specimen of Thyone nigra Joshua and Creed, 1915 from McHaffie Reef, Westernport Bay, with calcareous ring eviscerated (NMV F151855, photo by John Eichler).

Figure 21. SEM images of ossicles from specimen of Thyone nigra Joshua and Creed, 1915 (NMV F151855). Mid-body wall tables and tube foot support tables with narrow curved discs.