Ophiothrix fragilis

Glück, Franziska U., Stöhr, Sabine, Bochert, Ralf & Zettler, Michael L., 2012, Brittle stars (Echinodermata: Ophiuroidea) from the continental shelf off Angola and Namibia, Zootaxa 3475, pp. 1-20 : 14-15

Ophiothrix fragilis (Abildgaard in O.F. Müller, 1789)

Fig. 6 C, D

West African records. Ophiothrix rubra: Studer 1882: 25 ; Ophiothrix fragilis: Koehler 1907: 332 (f. lusitanica); 1914: 209; Mortensen 1925: 179; Cadenat 1938: 357; Cherbonnier 1962: 16; Tommasi 1967: 542; Madsen 1970: 213; Alva & Vadon 1989: 834; Ophiothrix quinquemaculata: Cherbonnier 1962: 18 .

Material examined. St. 66: dredge sampling, 9°33.702´S, 13°06.018´E; 2 specimens, 3–4 mm. St. BE08: grab sampling, 17°00.990´S, 11°27.048´E; 1 specimen, 6 mm. St. BE17: dredge sampling, 17°18.946´S, 11°43.389´E; 4 specimens, 2.5–3 mm. St. BE30: grab and dredge sampling, 17°23.415´S, 11°43.432´E; 4 specimens, 2.3–8.8 mm. St. BE03: grab sampling, 17°57.636´S, 11°46.104´E; 7 specimens, 2.5–3.3 mm. St. BE02: grab and dredge sampling, 18°11.442´S, 11°50.478´E; 34 specimens, 6–13 mm. St. BE01: dredge sampling, 18°23.118´S, 11°55.290´E; 3 specimens, 1,5– 5.8 mm. Depth: 20– 117 m.

Diagnosis. This species is known to be strongly polymorphic. There is great morphological diversity among the specimens found on the West African shelf, especially with respect to the disc armature (length, shape and patterns of spinelets). The radial shields are naked, rarely with granules or spinelets and then only sparsely covered. Arm spines and jaw are fairly similar to Ophiothrix congensis .

Distribution. Ophiothrix fragilis is an East Atlantic species with a distribution from Iceland and the Lofoten to South Africa. It is also common in the Mediterranean Sea. It occurs from the littoral zone down to approximately 1250 m.

Figures

FIGURE 6. A, B, Ophiothrix congensis; A, dorsal aspect; B, ventral aspect. C, D, Ophiothrix fragilis C, dorsal aspect; D, ventral aspect. E, F, Ophiura (Dictenophiura) carnea skoogi; E, dorsal aspect; F, ventral aspect. G, H, Ophiura grubei; G, dorsal aspect; H, ventral aspect. Scale bars 1 mm.