Type material. HOLOTYPE. USNM 749738 (alcohol specimen, spicule slide). 3.7 mm long, midbody height 0.7 mm. PARATYPE. USNM 749739 (histologic sections); off South Shetland Is., 62°41'S, 54°43'W, 210-220 m (U.S. Antarctic Res. Pgm. Stn 12-1003, 15.iii.64).
Type locality. Off South Sandwich Is., 56°19'-20'S, 27°28'-29'W, 148-201 m (U.S. Antarctic Res. Pgm. 1961-1972, Stn 22-1581, 6.iii.1966).
Diagnosis. Spiny (Fig. 3C)(see also Salvini-Plawen, 1978, fig. 288), cuticle thick (56 µm), epidermis thin (22 µm); spinelike epidermal spicules thick, long and wide, many greater than 160 µm long and up to 16 µm wide with an untapered, flat base (Fig. 5A); barbs to 170 by 14 µm; distally serrated spicules to 225 µm (see Salvini-Plawen, 1978, Fig. 92); short scimitar-like spicules common. Radular teeth approximately 40 µm in length, tips of lateral, fused denticles curved in histologic sections (Fig. 5B). Form of copulatory spicules not known.