Ophiophrura tripapillata ( Stöhr & Segonzac 2005 )

O’Hara, Timothy D. & Thuy, Ben, 2022, Biogeography and taxonomy of Ophiuroidea (Echinodermata) from the Îles Saint- Paul and Amsterdam in the southern Indian Ocean, Zootaxa 5124 (1), pp. 1-49 : 16

Ophiophrura tripapillata ( Stöhr & Segonzac 2005)

Fig. 4F–H

Ophioscolex tripapillatus Stöhr & Segonzac, 2005: 383–389 , fig. 3.

Ophiophrura tripapillata .— Martynov 2010: 77–78, fig. 53.

Material examined. MD 50 CP7, MNHN IE.2009.1572 (1). MD 50 DC64, MNHN IE.2009.1573 (1).

Distribution. Arctic (1311–1334 m), E Atlantic (849–1566 m). SPA (940–1680 m).

Remarks. The two specimens measure 5.5 mm dd (DC64) and 8.0 mm dd (CP7), the first is relatively intact ( Fig. 4F–H ) and the second is damaged and distorted with only part of the dorsal disc remaining. They are referred to Ophiophrura on the basis that the disc scales cover the radial shields, the lack of disc spines or granules, the flattened hollow arm spines, the presence of three elongated distal papillae on the jaw which correspond to two adoral shield spines and the distalmost lateral oral papilla, three to four tentacle scales, two of which are placed on the LAP and one to two on the VAP, arm spine articulations that are orientated obliquely to the LAP ridge and do not have a sigmoidal fold (after Martynov 2010).

Martynov (2010) referred three species to Ophiophrura which he separated on the basis of the shape of the oral shield, especially the shape of the distal margin (truncate vs obtuse vs lobed). However, this character is variable, even on the same animal. The current material is identified as O. tripapillata on the basis that it only has three (rarely four on the sixth segment) arm spines, and a cluster of tooth papillae at the jaw apex. Whereas O. imperfecta ( Clark 1915) and O. liodisca H.L. Clark, 1911 have four to five arm spines and a single row of papillae ventral to the teeth (see Martynov 2010 fig. 51–52).

Figures

FIGURE 4. (A–B) Anthophiura ingolfi, MNHN IE.2009.1609, A: dorsal and B: ventral views. (C–D) Amphiophiura sp., juvenile, MNHN IE.2009.1615, C: dorsal and D: ventral views. (E) Ophiomyces sp., juvenile, MNHN IE.2009.1577, lateral view. (F–H) Ophiophrura tripapillata, MNHN IE.2009.1573, F: dorsal view, G: ventral view and H: lateral arm view.