Ophiomusa lymani (Wyville Thomson, 1873 )

Nethupul, Hasitha, Stöhr, Sabine & Zhang, Haibin, 2022, New species, redescriptions and new records of deep-sea brittle stars (Echinodermata: Ophiuroidea) from the South China Sea, an integrated morphological and molecular approach, European Journal of Taxonomy 810 (1), pp. 1-95 : 28

Ophiomusa lymani (Wyville Thomson, 1873)

Figs 13A–G , 14

Ophiomusium lymani Wyville Thomson, 1873: 174–175 , fig. 33.

Ophiomusium lymani – Koehler 1904: 58; 1922b: 411, pl. 86 figs 5, 7–9. — H.L. Clark 1911: 107–108; 1923: 364. — Matsumoto 1915: 289. — Olbers et al. 2019: 72–74 fig. 51.

Ophiomusa lymani – Hertz 1927: 103–105.

Material examined

CHINA • 1 spec.; South China Sea, E of Hainan Island , seamount; 18°24.45′ N, 114°52.09′ E; depth 1911 m; 12 Mar. 2020; collection event: stn SC005; MSV Shenhaiyongshi leg.; preserved in -80°C; GenBank: MZ 198762 ; IDSSE EEB-SW0008 • 1 spec.; South China Sea, SE of Hainan Island , seamount; 17°39.60′ N, 110°36.42′ E; depth 917 m; 1 Sep. 2017; collection event: stn SC015; MSV Shenhaiyongshi leg.; preserved in -80°C; GenBank: MZ 198763 ; IDSSE EEB-SW0009 • 1 spec.; South China Sea, SE of Hainan Island , seamount; 17°06.00′ N, 110°58.20′ E; depth 1500 m; 23 Mar. 2018; collection event: stn SC017; MSV Shenhaiyongshi leg.; IDSSE EEB-SW0034 .

Remarks

We recorded three specimens from the South China Sea at 917 m to 1911 m depth. Disc diameter ranges from 17 to 20 mm. The specimens are similar to the holotype description by Wyville Thomson (1873) and to the first description from the South China Sea in Liao (2004) ( Fig. 13A–G ). The arm spine articulations are placed at the distal edge of the lateral arm plate ( Fig. 14A–D ). The vertebrae have a long zygospondylous articulation, a short, moderately large podial basin at the proximal end, and are small and narrow at the distal end. The dorsal end of the vertebrae is distally triangular and proximally flattened, with a long longitudinal groove along the midline, without furrow ( Fig. 14E–H ). The ventral end of the vertebrae has a broad midline longitudinal groove without an oral bridge ( Fig. 14G ). Ophiomusa lymani has been recorded from deep waters in both the East and South China Seas.

Distribution

130–4829 m depth. East China Sea, South China Sea, Arabian Sea, Indonesia, Australia, New Zealand, Chile, Gulf of Mexico, Caribbean, Atlantic Ocean and South Africa ( Olbers et al. 2019; OBIS 2021).

Figures

Fig. 13. A–G. Ophiomusa lymani (Wyville Thomson, 1873) (IDSSE EEB-SW0008). A. Dorsal disc. B. Ventral disc. C. Oral frame. D. Ventral arm base. E. Dorsal arm base. F. Ventral arm. G. Lateral arm plate with arm spines. H–L. Ophiomusa sp. (IDSSE EEB-SW0010). H. Dorsal disc. I–J. Ventral disc. K. Dorsal arm. L. Ventral arm. Abbreviations: as = adoral shield; ars = arm spine; dap = dorsal arm plate; gs = genital slit; lap =lateral arm plate; os = oral shield; rs = radial shield; tp = tentacle pore; vap = ventral arm plate. Scale bars: A = 10 mm; B = 15 mm; C–E = 2 mm; F, H–L = 1 mm; G = 500 µm.

Fig. 14. Ophiomusa lymani (Wyville Thomson, 1873), SEM (IDSSE EEB-SW0008). A–B. Internal view of lateral arm plate. C–D. External view of lateral arm plate. E–H. Vertebrae. E. Distal view. F. Proximal view. G. Ventral view. H. Dorsal view. Abbreviations: D = dorsal; Dist = distal; Prox = proximal; V = ventral. Scale bars: A, C, E–G = 500 µm; B, D = 300 µm; H = 800 µm.