Description (IDSSE EEB-SW 0020) MEASUREMENTS. Disc diameter 13 mm, length of arms 80 – 100 mm. DiSC. Disc slightly pentagonal (Fig. 20 A – B). Dorsal disc covered by thin, uncalcified, dark skin with surface of small projecting granules (Fig. 20 A). Ventral disc smooth, with few or no smooth granules (Fig. 20 B, E). Radial shields short, distally wider and widely separated (Fig. 21 F). Distal half of radial shields uncovered, bearing few granules on outer margin but do not reach periphery of disc (Fig. 21 F – G). Oral shields short, twice as wide as long and somewhat rhombic. Adoral shields short and wide, proximally meeting fully or some hardly meeting (Fig. 21 A). Teeth significantly larger than oral papillae. Lateral oral papillae broad, flat, rounded, transparent, distal edges break easily (Fig. 21 E). Number of lateral oral papillae varies among jaws, three per side, but some jaws have four oral papillae on one side (Fig. 21 E). Genital slits conspicuous and extending from distal end of oral shield to periphery of disc (Fig. 21 B). ARMS. Dorsal arm plate transversely oval with pointy corners, nearly twice as broad as long, covering only about half width of arm (Fig. 21 C). First ventral arm plate transverse diamond-shaped, with rounded angles, next two plates square with convex outer margin. Beyond third ventral arm plate, arm segments nearly semicircular with slight peak, covering one third of width of arm segment (Fig. 21 D – E). Tentacle scale absent on first arm segment and starts to appear from second or third arm segment (Fig. 21 E). Lateral arm plates stout, forming well defined spine ridge and meeting on ventral side except on first two arm segments (Fig. 21 D – F). Seven arm spines on an elevated ridge, four dorsal and three to four ventral. Dorsal arm spines often nearly two segments long, stout, nearly cylindrical and tapering to a blunt point (Fig. 21 G). Ventral arm spines smaller, thorny with hook-shaped tip, with a few spiny points on their adoral or proximal side (Fig. 21 H – I). Ventralmost arm spines on first few arm segments elongated and less hook-like, with rough surface but distalwards along arm developing into a short, little hyaline hook (Fig. 21 I). COLOR. Dark olivaceous green on dorsal disc, light brown color on radial shield, dorsal arm spine, and dorsal and ventral arm plate; dark reddish brown on oral papillae and ventral arm spine (Fig. 20 A – B). OSSiCLE MORPHOLOGY. Ventralmost arm spine short, thorny, with proximally oriented tip (Fig. 22 A). Arm spine articulation well developed, with volute-shaped perforated lobe except in dorsal- and ventralmost articulations (Fig. 22 B – C), with large muscle opening and small nerve opening (Fig. 22 B – C). Vertebrae with short zygospondylous articulation with a broad dorsal extension of lateral muscle flanges, distally abruptly truncated, dorsal median furrow moderately expressed, and podial basins short and large (Fig. 22 D – G). Middle segment of ventral vertebrae with deeply expressed furrow without oral bridge (Fig. 22 F).
