Ophiernus Lyman, 1878

Stöhr, Sabine, 2024, Taxonomic analysis of the genital plates and associated structures in Ophiuroidea (Echinodermata), European Journal of Taxonomy 933, pp. 1-98 : 66-67

Genus Ophiernus Lyman, 1878

Fig. 33

Type species

Ophiernus vallincola Lyman, 1878 .

Examined species

Ophiernus vallincola .

Oral GP

Not recognized among disc scales, may be absent.

Adradial GP

Long, narrow, bar-like, distal end slightly wider, with triangular process at ventro-abradial edge, ending in single condyle and curved groove with high edge.

Abradial GP

Blade-like flat, straight, articular structure slightly concave part on dorso-distal edge. More than half as long as adGP.

Oral shields

Coarse inner side, middle slightly thicker, madreporite with lateral pore in central part.

Radial shield

Articular structure with several minute spurs in middle of distal edge. No obvious muscle attachment patch on inner side.

Remarks

The ventral disc of O. vallincola is covered by delicate thin scales, embedded in thick skin. The oral shields distally overlay several scales, but none of them appeared to articulate with the oral shield. Oral genital plates may thus be reduced and are considered absent for now. External examination of species of Ophioleuce Koehler, 1904 suggests that oGP may be present in the shape of thin, elongated scales at the proximal end of the genital slit, abutting the oral shield distolaterally, but this needs to be verified when material for maceration is available.

Figures

Fig. 33. Ophiernidae O’Hara, Stöhr, Hugall, Thuy & Martynov, 2018, Ophiernus vallincola Lyman, 1878, SEM, unless otherwise noted. A. Genital plates in situ, adGP distally cut off during scan, micro- CT. B. adGP, lateral aspects. C. Radial shield, inner aspect. D. Same, close-up of articular structures. E. Oral shield, inner aspect. F. Madreporite, inner aspect. Scale bars: A–C, E–F =0.5 mm; D =0.1 mm.