Description (IDSSE EEB-SW 0003) MEASUREMENTS. Disc diameter 13.5 mm. DiSC. Flat, pentagonal. Entire dorsal disc covered by smooth, transparent, naked skin, but some small calcified scales between radial shields. Skin on center of dorsal disc becoming mesh-like and less smooth than at periphery of disc. Radial shields narrow, elongate, separate, covered by skin and extending to near disc center, but not meeting in center (Fig. 4 A). Ventral (oral) surface of disc also covered by smooth skin (Fig. 4 B). Oral shields slightly triangular. Adoral shield large, wider than long and slightly concave at distal margin, bordering proximal end of a depressed area near genital slit. Two tooth papillae, large and pointed, three smaller pointed lateral oral papillae, teeth also pointed. Two small, short, well separated genital slits in each ventral interradius (Fig. 4 C – D). ARMS. Simple, similar in size and length, five in number, with no abrupt change in width proximally, gradually tapering toward arm tip. No dorsal arm plates, arm covered with smooth translucent skin, leaving vertebrae visible (Fig. 4 E). Ventral and lateral arm plates concealed by thick skin but slightly visible on proximal arm (Fig. 4 F). Lateral arm plates meet at ventral midline, spines at ventrolateral margin extending onto ventral surface (Figs 4 F – G, 5 A – B). Starting from first free arm segment beyond disc, first two to three arm segments without spines at tentacle pores (Fig. 4 B – C); third to fourth arm segments with one or two short arm spines, becoming hook-shaped or with one secondary tooth (Fig. 4 C). Following tentacle pores with two to five hook-shaped arm spines and only uppermost arm spine elongated to simple hook shape, but ventralmost spines with one secondary tooth (Fig. 5 D). Length of all arm spines decreasing to approximately half length of corresponding arm segment in middle of arm. On distal third of arm, arm spines half as long as corresponding arm segment and transforming into hooks without secondary tooth, except ventralmost arm spine. Ventralmost arm spine becoming cylindrical, blunt with thorny tip, as long as one arm segment (Fig. 5 A – F). Tube foot elongate, cylindrical, slender, as long as an arm segment and positioned close to ventralmost arm spine (Fig. 5 A – C). COLOR. Dorsal disc light brown in center, naked skin between radial shields darker, radial shields whitish brown; ventral interradial areas light brown; arms whitish brown above and below (Fig. 4). OSSiCLE MORPHOLOGY. Lateral arm plate curved around vertebrae, bearing five spine articulations, each with small muscle opening, but lacking a separate nerve opening (Fig. 6 A – C). Arm spine articulations at distal edge of lateral plate, raised outwards, pointing distalwards. A depression on inner side of lateral arm plate (Fig. 6 B). Vertebrae with streptospondylous articulation, ventral side with a longitudinal groove along midline and no oral bridge (Fig. 6 D – H).
