Ophiostriatus sexradiatus Irimura, 1993

[Japanese name: Mutsuude-suji-kumohitode]

(Fig. 9C)

Ophiostriatus sexradiatus Irimura 1993: 161 –164, figs 1, 2.—Y. Fujita et al. 2015: 7, 98, fig.

Material examined. Okinawa Island (RUMF-ZE-02065[1], RUMF-ZE-02066[2], RUMF-ZE-02082[1]): “entrance” of the “Hedo-Dome” cave, under rocks or coral rubble, approximately 15 m depth, 22 May 2017. Ie Island (RUMF-ZE-02067[1]): “entrance” of the “Unnamed cave”, under coral rubble, approximately 18 m depth, 24 June 2017 .

Distribution. Ryukyu Islands, southern Japan. Depth range 18– 40 m.

Remarks. This species is identified as Ophiostriatus sexradiatus by virtue of having: six arms; disc densely covered small granules, aborally and a part of oral plates and adoral shields; four to five arm spines, slender and as long as the corresponding arm segment; two tentacle scales; striated lateral arm plates (Irimura, 1993).