Ophioscolex Müller & Troschel, 1842

Stöhr, Sabine, 2024, Taxonomic analysis of the genital plates and associated structures in Ophiuroidea (Echinodermata), European Journal of Taxonomy 933, pp. 1-98 : 27

Genus Ophioscolex Müller & Troschel, 1842

Fig. 10

Type species

Ophioscolex glacialis Müller & Troschel, 1842 .

Examined species

Ophioscolex glacialis .

Oral GP

Oval, thin, scale-like, articular notch at inner proximal edge, sitting slanted at proximal end of genital slit, pair widely separated, partly overlapped by oral shield, attached to oral and adoral shield.

Adradial GP

Bar-like, distal end slightly swollen, minute in relation to disc size, restricted to disc edge, far from oral shield. Articular structures not well defined, two or three ribs separated by grooves, a single condyle, proximal to it a process where abGP attaches.

Abradial GP

Flat, thin, elongated blade, dorsal edge straight, ventral edge convex. Proximally tapered, distally straight slanting edge without specific articular structures. ¾ as long as adGP. Attaching to adGP at a short distance from distal end, laying parallel.

Oral shields

Wider than long, externally with horizontal fold, internally with proximal horizontal ridge, demarcating distal portion, where oral GPs attach to a pore at each side. Madreporite as wide as long, folded horizontally, inner side with weak central horizontal ridge, and irregular processes extending into hollow interior, opening widely to one side.

Radial shield

Considered absent, but unidentified short ossicle present distal to abGP, attached to it, in ventral position.

Figures

Fig. 10. Ophioscolecidae Lütken, 1869, Ophioscolex glacialis Müller & Troschel, 1842, SEM, unless otherwise noted. A. Oral shield, madreporite, oral genital plates in situ (lightly bleached), digital image. B. adGP, adradial aspect. C. adGP, abradial spect. D. adGP, distal end. E. abGP. F. adoral shield with oGP attached. G. oGP. H. Oral shield, inner aspect. I. Madreporite, inner aspect. Scale bars: 0.5 mm.