Thyonidiella kungi O’Loughlin, 2012

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 : 289

Thyonidiella kungi O’Loughlin sp. nov.

Figures 1d , 8

Material examined. Holotype. Australia, Bass Strait , VIMS 81 –T–1, NZOI RV Tangaroa stn 176, 38°54.3'S, 147°13.4'E, 58 m, coarse shell, 18 Nov 1981, NMV F76637 .

Paratypes. Type locality and date, NMV F174910 (1) ; VIMS 81 – T–1 stn 171, 38°53.7'S, 147°55.2'E, 71 m, shelly sand, 17 Nov 1981, NMV F76635 (3) ; VIMS 81 – T–1 stn 177, 38°53.7'S, 147°06.5'E, 58 m, coarse shell, 18 Nov 1981, NMV F76638 (5).

Other material. VIMS 81 –T–1 stn 161, 39°47.3'S, 147°19.3'E, 60 m, muddy shell, 14 Nov 1981 , NMV F76636 (1) ; VIMS 81 –T–1 stn 174, 39°14.8'S, 147°31.5'E, 57 m, muddy shell, 18 Nov 1981 , NMV F76639 (5, very small) .

Diagnosis. Up to 16 mm long, up to 5 mm diameter (preserved, tentacles withdrawn), cylindrical body, rounded end orally, tapered to rounded end anally, thick soft body wall; external anal scales not detected; 15 tentacles in 2 series, 5 outer pairs large, 5 single inner small; complete spaced cover of tube feet, diameter up to about 0.2 mm; calcareous ring with 10 posterior composite tapering projections arising in pairs from radial plates only, posterior projections free thin tails each comprising about 5 elongate plates, ring not tubular, anterior radial plate narrowing slightly with deep central split, lacking lateral small notches, interradial plates not composite; single polian vesicle; longitudinal muscles flat, not divided.

Mid-body dorsal wall lacking ossicles; tube foot ossicles endplates and support ossicles only, endplates with denticulate margin, irregular sub-equal perforations, diameters up to 184 µ m, endplate support ossicles dumbbell-shaped, distally perforate with denticulate margin, up to 120 µ m long; tentacles with rods and rosettes, larger rods dumbbell-shaped, widened and perforate distally with denticulate margin, up to 304 µ m long, rosettes up to 88 µ m long; anal ossicles tube foot endplates and support rods, tentacle-like rods, rosettes, 5 scales comprising base up to 320 µ m wide with digitiform column up to 240 µ m long, base and column comprising massed short branched rods.

Specimen 3 mm long with radial tube feet; cucumariid ring lacking posterior prolongations; mid-body ossicles solid 4-pillared tables, irregular multi-perforate discs up to 184 µ m long, high spires with 4 cross connections, up to 136 µ m high; mid-body tube feet with endplates up to 152 µ m diameter, perforations small centrally, large peripherally, margin denticulate, endplate support rods dumbbell-shaped, up to184 µ m long.

Colour (preserved). Body pale brown.

Etymology. Named for the Taiwanese FRV Hai Kung that conducted part of the survey of the benthic marine fauna of eastern Bass Strait for the former Victorian Institute of Marine Sciences.

Distribution. Eastern Bass Strait, 38– 40°S, 147– 148°E, 58–71 m, coarse shell, mud and sand.

Remarks. Thyonidiella kungi O’Loughlin sp. nov. is distinguished from other southern Australia Phyllophoridae species in the key (above).

Figures

Figure 1. Photos of preserved type specimens. a, Lipotrapeza eichleri O’Loughlin sp. nov. (holotype NMV F174906); b, Lipotrapeza eichleri calcareous ring (paratype NMV F161502); c, Lipotrapeza litusi O’Loughlin sp. nov. (holotype WAM Z13475); d, Thyonidiella kungi O’Loughlin sp. nov. (holotype NMV F76637) (insert: form of the calcareous ring plates); e, Phyllophorella notialis O’Loughlin sp. nov. (holotype NMV F132691) (insert: form of the calcareous ring plates); f, Phyllophorella notialis calcareous ring (holotype).

Figure 8. SEM images of ossicles from specimens of Thyonidiella kungi O’Loughlin sp. nov. Tentacle rosettes and rods (left; holotype NMV F76637); endplate, dumbbell-shaped endplate support ossicles, and 4-pillared tables, from body wall of a juvenile (3 mm long; NMV F76639).