Ophiuroglypha fendouzhe Nethupul & Stöhr & Zhang 2023, sp. nov.
Creators: name: Nethupul, Hasitha
name: Stöhr, Sabine
name: Zhang, Haibin
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Echinodermata
Ophiuroidea
Ophiurida
Ophiopyrgidae
Ophiuroglypha
Ophiuroglypha fendouzhe

description: Ophiuroglypha fendouzhe sp. nov.
urn:lsid:zoobank.org:act: 31A4A22F-7F61-4510-BF10-67851B458559
Figs 1–5
Diagnosis
Disc pentagonal, covered by large irregular overlapping scales. Radial shields broad, slightly wider than long, triangular, barely connected to each other at distal end, and proximal half separated by one elongated disc scale (Fig. 3A–C). Ventral disc covered by large, overlapping scales, slightly larger than dorsal disc (Fig. 3D). Jaw slender, large, contiguous, pair of pointed ventralmost teeth at apex, and up to five lateral oral papillae (Fig. 3E). Second oral tentacle pore large, opening outside mouth slit with four adoral shield spines and five ventral tentacle scales (Fig. 3E–F). Arms slender. Dorsal and ventral arm plates separated (Fig. 3F–H). Tentacle pores absent after seven or nine arm segments (Fig. 3I).
Etymology
The specific name is dedicated to the manned submersible vessel ‘Fendouzhe’, which collected the specimen.
Material examined
Holotype PHILIPPINE SEA • central rift zone; 16º56.74′ N, 129º44.33′ E; depth 7729 m; 20 Sep. 2021; collecting event: stn. SC043; Fendouzhe msv leg.; GenBank: ON783074; preserved in 95% ethanol; IDSSE-EEB-SW0250.
Paratypes
PHILIPPINE SEA • 1 specimen; same collection data as for holotype; GenBank: ON783074; preserved in 95% ethanol; IDSSE-EEB-SW0251 • 3 specimens; same collection data as for holotype; preserved at -80°C; IDSSE-EEB-SW0252 to IDSSE-EEB-SW0254.
Description
MEASUREMENTS. Disc diameter 10 mm, arm base width 0.9 mm, and arm length 56 mm (Fig. 3).
DISC. Disc pentagonal, covered by large irregular, and polygonal overlapping scales (Fig. 3A–C). Centrodorsal primary plate rounded in disc center (Fig. 3C). Radial shields broad, slightly wider than long, triangular, barely connected to each other at distal end, sharp pointed proximal edge, straight distal edge, and proximal half separated by one elongated disc scale (k-plate) (Fig. 3A, C–D). Median distal interradial area of disc formed by four to five large scales (⅓ larger than other dorsal disc scales), most of them rounded rectangular (Fig. 3C). Ventral disc covered by large, overlapping scales, slightly larger than on central dorsal disc (Fig. 3B, E–F). Distal end of genital slit bordered by small pointed genital papillae forming arm comb (Fig. 3E–F). Oral shield as wide as long, triangular, slightly convex at distal end, and connected to genital slit (Fig. 3E). Adoral shields small, narrow, rectangular, slightly curving outward from oral shield, contiguous proximally, and distally connected to first lateral arm plate (Fig. 3E). Jaw slender, large, contiguous, with pair of pointed infradental papillae at apex, and spearhead-shaped teeth (Fig. 3E). Up to five lateral oral papillae. Distalmost papilla (ventral compartment plate) much broader than others, and proximal two to three papillae spearhead-shaped to oval, and distal lateral oral papilla (buccal scale) lesspointed and broader (Fig. 3E). Second oral tentacle pore large and opening outside mouth slit, with five ventral tentacle scales and four adoral shield spines at each side. Genital slits conspicuous and extending from oral shield to disc periphery (Fig. 3E–F).
ARMS. Five slender, and non-moniliform arms. Dorsal arm plates small, diamond-shaped, straight to slightly fan-shaped with convex distal edge, pointed proximal edge, as wide as long, and widely separated, except on first and second arm segments (Fig. 3D, G). First two ventral arm plates slightly wider than long, pentagonal, and contiguous. Following ventral arm plates wider than long, pentagonal to triangular, distally straight to slightly curved, proximally triangular, and increasingly separated along arm (Fig. 3E–F, H). Lateral arm plate with mostly three and rarely four arm spines. All arm spines small, smooth, pointed tip, similar in length, and approximately ½ arm segment long (Fig. 3G–L). Distally, middle arm spine slightly curved inwards (Fig. 3I–L). First tentacle pore with three or four tentacle scales (Fig. 3F–L). Second and third tentacle pores with four to two tentacle scales (Fig. 3F). Fourth to fifth tentacle pores with three to one tentacle scales (Fig. 3F). Number of tentacle scales decreases to one scale, and absent after seven or nine arm segments (Fig. 3H, L).
COLOR. Creamy white in alcohol specimen (Figs 3, 5).
OSSICLE MORPHOLOGY. (IDSSE-EEB-SW0251) Three arm spine articulations placed at distal edge of lateral arm plate, with clear muscle opening and small nerve opening (Fig. 4A–B). Tube foot pore developed as large within-plate perforation on lateral arm plates from base to middle part of arm, where tentacle scales begin to disappear from arm segments (Fig. 4A–B). Middle half of inner side of lateral arm plate with depression and two round knobs (Fig. 4C). Vertebrae with moderate zygospondylous articulation, proximal end with podial basins (Fig. 4D–H). Dorsal side of vertebrae distally triangular and proximally slightly curved, shallow longitudinal groove along midline (Fig. 4F–H). Ventral side of vertebrae with long and broad ambulacral groove with pair of lateral ambulacral canals (Fig. 4F–H).
Paratype variations
Four paratype specimens were collected from the same location. They are similar to the holotype (disc diameters 8.0–10.0 mm), but one paratype has a sub-pentagonal disc and an obvious round centrodorsal primary plate (Fig. 5A).All paratypes are identical to the holotype with respect to the other morphological characters and this small variation is considered intraspecific (Fig. 5).
Distribution and habitat
So far only known from the type locality.
description: Published as part of Nethupul, Hasitha, Stöhr, Sabine & Zhang, Haibin, 2023, Deepest known novel species of the genus Ophiuroglypha Hertz, 1927 (Echinodermata: Ophiuroidea) from the central rift zone, Philippine Sea, pp. 167-185 in European Journal of Taxonomy 891 on pages 176-178, DOI: 10.5852/ejt.2023.891.2281, http://zenodo.org/record/8382615