Ophiosphalma spinulosum (Koehler, 1922) .

Figures 60 a, b

Ophiomusium spinulosum Koehler, 1922

Lectotype USNM E190, and 2 paralectotypes E189 Albatross stations 5651 and 5650, respectively, Gulf of Bonin, Celebes, 987m.

Main features: Upper surface of disc and arms covered with short “crusty” spinules. None on ventral surface. Many scales of equal size in ventral and dorsal interradii. Radial shields small, roughly oval and widely separated by 5–6 rows of small scales. Smooth contours on arms, but joints rather constricted. Upper arm spines have double distal hook. Three pairs exposed tentacle pores with up to 4 scales each. Genital slits run to distal end of second arm plate, papillae each side. Oral papillae separated.