New dendrochirotid sea cucumbers from northern Australia (Echinodermata: Holothuroidea: Dendrochirotida) P. Mark O’Loughlin Melanie Mackenzie Didier Vandenspiegel Memoirs of Museum Victoria 2014 2014-12-31 72 5 23 585NG O'Loughlin P. Mark O’Loughlin & Melanie Mackenzie & Didier Vandenspiegel 2014 [147,470,536,559] Holothuroidea Phyllophoridae Triasemperia GBIF Animalia Dendrochirotida 11 16 Echinodermata species stola sp. nov.   Figures 9, 10.     Materialexamined. Holotype. N Australia, Joseph Bonaparte Gulf, 12.32°S 129.94°E, shell and sand substrate, RV Solander,  46 m, AIMS& GA,  5 Aug 2010, NMVF174889 (GA specimen 29084, SOL 5117, 013BS010; UF tissue lot MOLAF1541).   Paratypes. NE Australia, Queensland, Yeppoon, dredged off Middle Island, 23.13°S 150.74°E,  9–37m, B. J. Smith,  6 Sept 1967, NMVF204083 (1); same data, NMVF204088 (1).   Description. Form cylindrical, elongate, upturned oral and anal ends, tapered orally, long taper anally, U-shape up to 45 mmwide (preserved); hard, thick, calcareous body wall, ‘prickly’ to touch; mouth anterior, anus posterior, lacking anal teeth; tube feet scattered over body, withdrawn, inconspicuous (preserved), diameters about 0.2 mm, paired radial series of tube feet on withdrawn introvert; 20 dendritic tentacles, 15 large, 5 inner small; calcareous ring composite, comprising small calcareous pieces, radial and inter-radial composite plates adjoin to create tubular ring, radial plates elongate with thin posterior distal prolongations adjoining inter-radial plate elongations, radial plates with median division for most of the length, inter-radial plates with deep posterior notch; single polian vesicle; gonad tubules with numerous branches; respiratory trees extending throughout the coelom. Ossicles throughout body wall densely crowded thick tables, table discs triangular, typically with 6 large marginal knobs and 6 small perforations, discs 80–120 µm wide, spires with 3 pillars and 6 pointed spines distally, disc width and spire height sub-equal. Introvert and tube feet with tables, rods, endplates; tables smaller, irregular, some lacking spires, perforations up to 19, discs up to 56–104 µm wide; smooth rods with distal ends enlarged and perforated, up to 120 µm long; endplates with diameters about 136 µm, tube foot support ossicles tables only. Tentacles with rods, rosettes, tables; fine to thick smooth rods with swollen perforated ends; tables rare, form regular or irregular, some not knobbed, discs up 96 µm wide.  Figure 8. SEM images of ossicles from the holotype of  Massinium keesingiO’Loughlin sp. nov.(NMV F203008). A, peri-anal body wall tables and endplate fragment, discs with smooth margins, spires with 1 or 2 pillars (scale bars 10 µm); B, oral disc tables, table discs with smooth margin, spires with single or 2 partly fused pillars, apical spines short and blunt (scale bars 10 µm); C, tentacle rods (scale bars 10 µm). Live colour red-brown to brown, preserved colour brown to off-white with residual violet colouration.   Distribution. Northern Australia, from Joseph Bonaparte Gulf to Yeppoon Queensland, 9– 53 m.   Etymology. Named  stolawith reference to the genus  Stolusthat has species with heavily knobbed button-like ossicles that are similar to the table discs of this species.   Remarks. The distinguishing morphological character of  Triasemperia stolais the presence of table spires with three pillars. The calcareous ring and ossicles are similar to those of  Stolus crassus Liao and Pawson, 2001, but  S. crassusfrom the South ChinaSea is described as having 10 tentacles and only 2 pillars in the table spires. Family  Thyonidiidae Heding and Panning, 1954( sensu Smirnov 2012)  Remarks. Heding and Panning (1954)initially described the Thyonidiinaeas a sub-family within the Phyllophoridae Östergren, 1907. Based on the absence of posterior segmented prolongations on the calcareous ring Pawson and Fell (1965)transferred the Thyonidiinaeto a sub-family within the Cucumariidae Ludwig, 1894. Based on the presence of more than 10 tentacles and table ossicles Smirnov (2012)raised Thyonidiinaeto family status as Thyonidiidae. The plate ossicles in  ParathyonidiumHeding (in Heding and Panning), 1954and “reduced” ossicles in  Athyonidium Deichmann, 1941and  Patallus Selenka, 1868suggested to Smirnov (2012)that these genera were probably unrelated to the genera with tables. 1851456623 2010-08-05 AIMS, NMV RV Solander Australia 46 -12.32 Material 776 129.94 Joseph Bonaparte Gulf 11 16 MOLAF1541 1 holotype 1851456620 1967-09-06 NMV B. J. Smith Australia 23 -23.13 Middle Island 754 150.74 Yeppoon 11 16 1 Queensland paratype 1851456716 [329,607,848,868] 1967-09-06 NMV B. J. Smith Australia 23 -23.13 Middle Island 754 150.74 Yeppoon 11 16 1 Queensland paratype