Protankyra torquea O’Loughlin, 2016

O’Loughlin, P. Mark, Harding 1, Caroline & Paulay, Gustav, 2016, The sea cucumbers of Camden Sound in northwest Australia, including four new species (Echinodermata: Holothuroidea), Memoirs of Museum Victoria 75, pp. 7-52 : 43

Protankyra torquea O’Loughlin sp. nov.

Zoobank LSID. http://zoobank.org/ urn:lsid:zoobank.org:act:

94FD3258-AAE8-48F3-939F-444D8ECC70FD

Table 1; appendix 1; figure 28

Material examined. Holotype. Northwest Western Australia, Kimberley Region, Camden Sound , WAMSI 1.1 .1, RV Solander, sled, site no SOL_48, WAM station no 4, barcode 10000142, from -15.39822 124.28823 23.2 m to -15.39864 124.28950 28.6 m, 15 Mar 2015, WAM Z89071 .

Description (preserved in 95% ethanol). Anterior end only of synaptid species, 26 mm long, up to 16 mm diameter; body wall firm to hard, thick, opaque, not translucent; tentacles 12, trunks elongate, each with two pairs of closely placed distal digits, distal end of tentacles with short, thick papilla-like end; four polian vesicles detected; ciliated funnels not detected at base of dorsal mesentery or along coelomic inter-radii; longitudinal muscles broad, thick, rounded, undivided.

Body wall ossicles anchors, anchor plates, short rods, miliary granules. Anchors irregular in form, similar sizes, up to 304 µm long, base of stocks variably indented, variably finely toothed, lateral ends of stock with raised rounded elevations, shaft variably constricted near base, anchor vertex lacking knobs, arms with 3–5 outer anteriorly pointed spines. Anchor plates irregularly heart-shaped, breadth and height sub-equal, size slightly variable, plates 230–260 µm long, perforations (excluding basally) up to about 30, irregular in size, basal perforations numerous and small, fine teeth on inner margin of perforations numerous to rare to absent, plates lacking significantly larger central perforations, margin of plates incomplete and irregular, irregular bow across posterior end of plates. Short curved rods abundant, of variable form, some curved inwards distally, some with distal swellings, some bluntly denticulate on inner margin, rods up to about 30 µm long. Some miliary ‘granules’ found in body wall, not abundant, thin oval flat plates, some dumbbell shaped, up to about 30 µm long. Tentacles with miliary ‘granules’ and rods, as in body wall. Longitudinal muscles with abundant miliary ‘granules’ only, ‘granules’ as in body wall and tentacles.

Live body colour off-white with irregular red-brown transverse patches, tentacle trunks as for body, digits pale yellow; preserved body colour off-white with irregular pale brown patches.

Distribution. Northwest Western Australia, Kimberley Region, Camden Sound, 23– 29 m.

Etymology. Named torquea from the Latin torqueo (irregular), with reference to the irregular form of the typically incomplete margin of anchor plates, and irregular form of the anchor stock bases.

Remarks. The specimen comprises an anterior end only, is strongly contracted, and the alimentary canal and mesentery are mostly eviscerated. These factors might account for the apparent absence of ciliated funnels. Three Protankyra species are reported from northern Australia by Rowe (in Rowe & Gates 1995): P. insolens ( Théel, 1886) (type locality Arafura Sea, north of Camden Sound); P. similis ( Semper, 1867) (type locality the Philippines); P. verrilli ( Théel, 1886) (type locality Torres Strait, NE Australia). Both P. insolens and P. verrilli were found in Camden Sound and are reported here. Each fits well with the description and illustration by Théel (1886). Amongst Protankyra species, Protankyra torquea O’Loughlin sp. nov. is closest to P. verrilli in morphological characters, but P. verrilli lacks rods in the body wall, is smaller, has a thin body wall, and lacks colour in the preserved state.