Ophiophthalmus normani (Lyman, 1879)

Fig. 12A‒F

Ophiacantha normani Lyman, 1879: 58‒59, pl. 15, figs. 414‒416.—Lütken & Mortensen 1899: 170‒171, pl. 16, figs. 1‒4.— H.L. Clark 1911: 215‒217.— Boolotian & Leighton 1966: 7‒10, fig. 31.— Lambert & Austin 2007: 80‒81, figs. 34‒35.

Ophiophthalmus normani . Koehler 1922: pl. 9, fig. 5‒6.— Kyte 1969a: 1738.— Hendler 2018: 212‒213, fig. 17.— Nethupul et al. 2022: 196.

Material examined. 2,254 individuals at 14 stations. TALUD VIII, Sta. 3, 5 ind. (ICML-EMU-11198) and 5 ind. (ICML-EMU-11202-A); Sta. 10, 1 ind. (ICML-EMU-11199-A); Sta. 16, 2 ind. (ICML-EMU-11199-B). TALUD IX, Sta. 21B, 1 ind. (ICML-EMU-11202-B). TALUD X, Sta. 9, 412 ind. (ICML-EMU-11196); Sta. 10, 2 ind. (ICML-EMU-9015), 9 ind. (ICML-EMU-11200), 7 ind. (ICML-EMU-11201), and 941 ind. (ICML-EMU-11219); Sta. 12, 11 ind. (ICML-EMU-11197). TALUD XIII, Sta. B, 1 ind. (ICML-EMU-11203-A); Sta. 34, 3 ind. (ICML-EMU-11203-B); Sta. 37, 1 ind. (ICML-EMU-13000). TALUD XVIB, Sta. 19, 2 ind. (ICML-EMU-11205); Sta. 22, 47 ind. (ICML-EMU-11204); Sta. 23, 22 ind. (ICML-EMU-11206); Sta. 27, 19 ind. (ICML-EMU-11207), 54 ind. (ICML-EMU-11208), 704 ind. (ICML-EMU-11223), and 5 ind. (ICML-EMU-11688).

Comparative material. Ophiacantha normani Lyman, 1879, syntypes, 4 ind.: MCZ OPH-1971 (Supplementary file 2).

Description (ICML-EMU-11219). DD = 16 mm. Disc circular. Dorsal disc covered by scales and scattered granules. Primary plates not evident. RS oval, separated (Fig. 12A). Ventral interradii covered by scattered granules, longer than dorsal granules. Genital slits with numerous imbricated scales (Fig. 12B). OSh broader than long, slender, diamond-shaped with rounded edges. Madreporite with a rounded depression. AdSh longer than broad, slender, curved, separated from each other. Jaws bearing three papillae at each side; AdShSp elongated, pointed; 2AdShSp similar in shape to AdShSp; IPa similar to AdShSp and 2AdShSp but with widened base. vT pointed, wider than IPa (Fig. 12C). Arms gradually narrowing distally. DAP broader than long, fan-shaped, distal edge with a conspicuous row of pointed granules, meeting on the first segments and separated distally (Fig. 12D). VAP slightly broader than long, pentagonal with a distal notch, separated from each other. LAP with four ArSp, large (approximately three arm segments in length), smooth, dorsalmost the longest. Tentacle pores with one pointed TSc (Fig. 12E). Color pattern brown (ethanol preservation) (Fig. 12A‒F).

Habitat and distribution. Japan, the Okhotsk Sea, the Bering Sea, Alaska, USA, Mexico, Costa Rica, and Peru (Lyman 1879; Lambert & Austin 2007; Granja-Fernández et al. 2015; Granja-Fernández & Hooker 2020); 37‒ 3,000 m depth (Lambert & Austin 2007), muddy substrates (Lütken & Mortensen 1899). The material examined was collected off western Baja California and in the Gulf of California; 465‒ 2,195 m depth.

Remarks. Ophiophthalmus normani is easily identifiable by its DAP with a conspicuous row of pointed granules on the distal edge, and its disc with scales and granules (except on the radial shields).