Macrophiothrix oliveri (Benham, 1911)

Mills, V. Sadie & O'Hara, Timothy D., 2013, Ophiuroids (Echinodermata; Ophiuroidea) of biogenic habitats on the continental shelf of New Zealand, Zootaxa 3613 (5), pp. 401-444 : 435

Macrophiothrix oliveri (Benham, 1911)

( Fig. 15 )

Ophiothrix oliveri Benham, 1911: 154 –156, figs. 14–17.—Clark, H.L., 1915: 276.—Clark, A.M., 1967: 647. Ophiothrix (Ophiothrix) oliveri .—Mortensen, 1924: 118–120, fig. 8.

Macrophiothrix oliveri .—Hoggett, 1990: 192–194, figs. 3.22e –i, 3.23e –g.

Material Examined. Bay of Islands. KAH0907/194, NIWA 77880 (1). TAN0906/2, NIWA 77863 (1). TAN0906/ 60, NIWA 55192 (86). TAN0906/81, NIWA 55440 (3). TAN0906/96, NIWA 77862 (1). TAN0906/99, NIWA 55683 (1). TAN0906/102, NIWA 55737 (1). TAN0906/170, NIWA 77861 (2). TAN0906/240, NIWA 57508 (20). East Coast North Island. TAN1108/197, NIWA 77785 (3). TAN1108/213, NIWA 77800 (3). TAN1108/217, NIWA 77814 (2). TAN1108/239, NIWA 77816 (1). TAN1108/250, NIWA 75543 (1). TAN1108/253, NIWA 75593 (2). TAN1108/268, NIWA 77783 (30). TAN1108/275, NIWA 77812 (3). Far North. TAN0906/159, NIWA 56591 (10). TAN1105/60, NIWA 73395 (1). Three Kings Islands. TAN1105/35, NIWA 77846 (8). TAN1105/42, NIWA 77845 (2). TAN1105/53, NIWA 73324 (2). TAN1105/69, NIWA 77831 (18). TAN1105/70, NIWA 77815 (2).

Comparative Material. Macrophiothrix oliveri (Benham, 1911) : Duncombe Bay, Norfolk Island, 29° 0´S, 167° 55´E, 15 m, 25/9/1976, MV F96553 (1). NZOI/K797, off L'Esperance Rock, 31° 20.82´S, 178° 49.2´W, 55 m, 19/7/1974, NIWA 79573 (20). NZOI/P968, Raoul Island, Kermadec Chain, 29° 14.7´S, 177° 52.32´W, 10 m, 11/6/1980, NIWA 79568 (1). NZOI/T260, off L'Esperance Rock, 31° 20.802´S, 178° 49.602´W, 68 m, 28/3/1982, NIWA 79564 (12).

Diagnosis. Disc densely covered in glassy trifid-multifid spinelets, obscuring disc plates and radial shields. Distal edges of white radial shields visible beneath spinelets. Dorsal arm plates twice as wide as long, truncate fan shaped, light pinkish purple interspersed with a darker plate every 2–3 segments, all with variable white blotch on distal border. Ventral disc and arm surface creamy white. Six transparent arm spines, 3–4 arm segments, 4th spine longest, reducing to less than a segment ventrally, with thorny edges.

Description. See Mortensen (1924).

Distribution. Kermadec and Norfolk Islands (1–157 m), northern New Zealand (37–205 m)

Remarks. This species was transferred to Macrophiothrix by Hoggett (1990) in an unpublished PhD thesis. Examination of the specimens here confirms this decision; the dorsal arm plates are in general twice as wide as long, similar to other Macrophiothrix species. Within Macrophiothrix, Hoggett (1990) distinguished M. oliveri by the length of the fourth-sixth arm spines from the top which are the longest in the series. On other species, the second-third arm spines are longest. This species has a restricted distribution along the north-east coast of New Zealand and around a few islands to the north.

Figures

FIGURE 15. Macrophiothrix oliveri (Benham, 1911) (NIWA 55683, TAN 0906 / 99) showing live colour, a: dorsal, b: ventral; Scale bar = 1 mm.