Ophioprium H.L. Clark, 1915

Martynov, Alexander, 2010, Reassessment of the classification of the Ophiuroidea (Echinodermata), based on morphological characters. I. General character evaluation and delineation of the families Ophiomyxidae and Ophiacanthidae 2697, Zootaxa 2697, pp. 1-154 : 87-90

Genus Ophioprium H.L. Clark, 1915

Figures 57A, B; 61–62

Ophioprium H.L. Clark, 1915: 214–215

Type species: Ophiacantha cervicornis Lyman, 1883 , by original designation Diagnosis. The disk is covered with numerous small, uniform scales and a thin skin layer. The radial shields are small, rounded, hardly conspicuous in dried specimens. The adradial and abradial genital plates are well defined. Details of the articulations of genital plates and radial shields are unknown. The genital slits are long and conspicuous, genital plates border more than half of the slits. The jaw bears numerous spiniform oral papillae, similar in shape to the small cluster of ventralmost teeth. Two adoral shield papillae and one adjacent oral papilla of each jaw are narrow, spiniform, 3–4 times longer than the oral papillae, placed around the second tentacle pore. The half-jaws, judged from the length of the dental plate, are high. The dental plate is small and elongated, without folds and with few rounded sockets, alternately placed. The teeth are spiniform and few in number (besides the apical papillae there are 4–5 teeth). All teeth are similar in shape. The oral shield is lozenge-shaped with a distinct distal lobe. The adoral shields have distal bilobed wings, proximally tapered. Dorsal and ventral arm plates are well developed. The arm spine articulations are placed almost transversally in relation to the lateral plate. The muscle opening is larger than the nerve opening. A prominent distal perforated lobe occupies the distal part of the articulation. The sigmoidal fold is absent. The arm spines are long, flattened, solid over most of their length but contain some holes of various sizes, not hooked distally. The tentacles scales are thin, spiniform, placed on both lateral and ventral arm plates. The tentacles pores are large. The vertebrae have a rounded distal keel, with deep dorsal medial furrow. The articulation is zygospondylous. The podial basins are large.

Remarks. Several different species have been included in the genus Ophioprium (H.L. Clark 1915; Baker 1979; Baker & Devaney 1981). Paterson (1985) excluded from this genus Ophioprium larissae Baker, 1979 , O. kapalae Baker, 1979 , O. axiologus (H.L. Clark, 1909) and O. rosea ( Lyman, 1878) but retained O. imperfectum H.L. Clark, 1915 . Re-examination of the holotype of O. imperfectum ( Figs 52F, H–J) during the present study reveals considerable differences from the type species of the genus Ophioprium . Thus, only two species remain within the genus. Both species are very similar and their taxonomy needs further study. Verrill’s authorship of the genus Ophioprium was incorrectly listed by Paterson (1985).

Material studied. Ophioprium cervicornis ( Lyman, 1883) , Holotype MCZ 2043 ( Figs 57A, B); Ophioprium permixtum ( Koehler, 1914) , Holotype USNM 032296 ; one specimen USNM E 05300 ( Figs 61; 62) .