Ophiophycis richardi, Mcknight, Donald G., 2003

Mcknight, Donald G., 2003, New brittle­stars (Echinodermata: Ophiuroidea) from New Zealand waters, Zootaxa 352, pp. 1-36 : 16-18

Ophiophycis richardi n.sp. Fig. 4 : A, B, E.

Material examined: NIWA Stn D39 (8).

Depth Distribution: 549 m.

Geographic Distribution: This species is recorded from southwest of the Auckland Islands.

Description: Holotype: disc diameter 4 mm, arms broken, longest at about 3 mm. Marginal fringe distinct. Disc pentagonal, domed on dorsal surface, ventral surface flat. Dorsal surface of disc covered by 16 plates; centrodorsal pentagonal, sides radial, surrounded by 5 pentagonal radial plates, which it slightly overlaps; outer angle of radial plate separates inner end of radial shields; one margin of a radial shield usually overlaps that of a neighbour. Radial shields longer than wide, blunt proximally and distally, in contact for over 1/2 of length, separated by flat first dorsal armplate; one shield sometimes overlapping its neighbour. In dorsal interradii, 2 plates extend to margin; inner is elongate, much longer than wide, rectangular; marginal plate is more or less ovoid; outer margin usually with a flat, bluntly pointed spine. Ventral surface of disc with 2 narrow plates distal to oral shield, these extending to near margin but not reaching it; beyond is spine of marginal dorsal interradial plate. Oral plates small, more or less pentagonal, pointed proximally. Adoral plates larger, meeting broadly within, more or less proximal to oral shield. Oral plates with low, fused papillae along oral slit, sometimes the proximal part with 1–2 low 'bumps'; a single small, pointed papilla at jaw apex, teeth concealed.

Arms wider than high at base, distinctly flattened. Dorsal armplates present to end of broken arm; first 2 dorsal armplates contiguous, first separates distal ends of radial shields, together the 2 plates form a triangle, pointed proximally, wider than long; succeeding plates widely separated, small and triangular, wider than long, much smaller, minute at end of broken arm. First lateral armplate confined to ventral surface, others visible dorsally, second is small in dorsal view, lying lateral to radial shields; third pair of laterals meet dorsally behind second dorsal armplate; succeeding lateral plates meet broadly on dorsal midline. On ventral surface first lateral plates extend about 2/3 distance to margin, and have 2 flattened spines; second plates reach margin, with 3 flattened spines; first 2 lateral plates do not touch, and between spines of each plate is the flat projection from dorsal interradial plate; third to fifth plates with 3 flat spines; first to fourth plates meet narrowly on ventral midline of arm, fifth plates unite for over 1/2 of length, distal plates for almost all of length. Ventral armplates separated throughout, decreasing in size from the first, minute from the fifth, persisting to end of broken arm. Proximal plates longer than wide, pointed proximally and distally, distal plates triangular. Five pairs of tentacle­pores present, largest proximally, all conspicuous; lateral margins of ventral armplates concave around pore, with a single, flat, rounded tentacle­scale; scale rarely subdivided.

Etymology: This species is named for Mr Richard Garlick, NIWA, for introducing me to seamount mapping.

Holotype: Deposited in the NIWA collection, Wellington No. H­822 (Stn D39). Paratypes: Deposited in the NIWA collection, Wellington No. P­1374 (Stn D39). Colour: (Preserved specimens) the specimens are uniform white, on both dorsal and

ventral surfaces.

Remarks: This species is most closely related to the genotype, O. mirabilis Koehler. Ophiophycis richardi differs in having the centrodorsal and radial plates pentagonal, and lacks a median plate distal to the oral shield.

Figures

FIGURE 4: Ophiophycis richardi n. sp. holotype, disc diameter 4 mm. A: dorsal, B: ventral, E: armbase (SEM). Ophiophycis johni n. sp. holotype, disc diameter 5.5 mm. C: dorsal, D: ventral, F: armbase (SEM).