Gorgonocephalus cf. dolichodactylus Döderlein, 1911

Figs 11–12

Gorgonocephalus dolichodactylus Döderlein, 1911: 34–36, pl. 1 figs 4–5, pl. 7 figs 3, 4a–b.

Gorgonocephalus dolichodactylus – Döderlein 1927: 27, 52. — Matsumoto 1915: 73, fig. 20. — Baker 1980: 52, figs 18a, 20, 30. — Liao & Clark 1995: 171, fig. 75. — McKnight 2000: 45–46, pl. 20.

Material examined

CHINA • 1 spec.; South China Sea, Zhongsha Islands, seamount; 13°36.00′ N, 114°34.49′ E; depth 1340 m; 30 Mar. 2020; collection event: stn SC008; MSV Shenhaiyongshi leg.; preserved in -80°C; GenBank: MZ 198760; IDSSE EEB-SW0006 .

Remarks

The disc diameter was 67 mm. Our specimen is similar to the holotype description by Döderlein (1911) and the description in Liao & Clark (1995), but showed some morphological variations, especially on the disc (Fig. 11). Therefore, we hesitate to fully associate our specimen with G. dolichodactylus . The original description and the description in Liao & Clark (1995) mention small granules on both the dorsal and ventral disc, but the present specimen is completely naked except for the radial shields (Fig. 11A–E), which are covered by scattered granules (Fig. 11F).

Pedicellarial bands are formed by approximately 12 articulating tubercles at the curved distal end of the baseplate (Fig. 12B), and these articulations have a single foramen (Fig. 12C). The distal end of the baseplate internal side becomes curved with perforations on the ventral side of the baseplate (Fig. 12B–C). The vertebrae have a streptospondylous articulation with smooth lateral furrows and no oral bridge (Fig. 12D–H). The external side of the lateral arm plate has three separate tubercle-shaped articulations with a single opening and one large muscle opening at the edge. Gorgonocephalus dolichodactylus was first recorded from the South China Sea in southeastern Hainan, at a depth of 1100 m, in 1959.

Distribution

146–1357 m depth. South China Sea, Japan, Korea, Philippines, Australia and New Zealand (Liao 2004; OBIS 2021).