Ophiacantha sociabilis Koehler, 1897: 348

Stöhr, Sabine & O’Hara, Timothy D., 2021, Deep-sea Ophiuroidea (Echinodermata) from the Danish Galathea II Expedition 1950 - 52, with taxonomic revisions, Zootaxa 4963 (3), pp. 505-529 : 522

Ophiacantha sociabilis Koehler, 1897: 348 , pl. 8 figs 62–63.

Figure 4H

Material examined

INDIAN OCEAN • 8 specimens; off Kenya; 03°23’S, 044°04’E; 3960–3980 m; 13 Mar. 1951; Galathea II stn. 238; Globigerina ooze, NHMD-867440 • 7 specimens; Sri Lanka; 03°38’N, 078°15’E; 3310 m; 10 Apr. 1951; Galathea II stn. 281; Globigerina ooze; NHMD-867267, NHMD-867211 • 26 specimens; off Sri Lanka; 05°32’N, 078°41’E; 4040 m; 11 Apr. 1951; Galathea II stn. 282; blackish mud; NHMD-867291.

Remarks

The Galathea samples from the Indian Ocean identified as O. sociabilis differ from the Pacific and Antarctic specimens in having 4–5 pointed lateral oral papillae, the distal one not enlarged, the jaws are wider than in O. pacifica and the oral shield is longer and the lateral edges more rounded. Ophiacantha sociabilis was originally described from the Andaman Islands and Bay of Bengal ( Koehler 1897), and it seems advisable to preserve this name for the Indian Ocean population until more data are available.

Figures

FIGURE 4. A, B, Ophiacantha pacifica, largest syntype (11.6 mm dd), ZMUC OPH-000399. A, dorsal aspect, B, ventral aspect. C, D, Ophiacantha pacifica (originally identified as O. cosmica by Lütken & Mortensen (1899)), Albatross Exp. stn. 3414, NHMD (unregistered), C, dorsal aspect, D, ventral aspect. E, F, Ophiacantha cosmica, Galathea II stn. 601, NHMD-867169. E, small specimen (12.4 mm dd) with few oral papillae, F, large specimen (22.3 mm dd) with many oral papillae. G, Ophiacantha cosmica, Galathea II stn. 599, NHMD-867198, ventral aspect, H, Ophiacantha sociabilis, Galathea II stn. 281, NHMD-867267 or NHMD-86721, ventral aspect. OPa, oral papillae sensu lato, OS, oral shield, RS, radial shield, T, tooth. Scale bars = 1 mm.