Ophiologimus aiodipius Thuy 2013
- Dataset
- Temporary expansion to shelf depths rather than an onshore-offshore trend: the shallow-water rise and demise of the modern deep-sea brittle star family Ophiacanthidae (Echinodermata: Ophiuroidea)
- Rank
- SPECIES
- Published in
- Thuy, Ben (2013): Temporary expansion to shelf depths rather than an onshore-offshore trend: the shallow-water rise and demise of the modern deep-sea brittle star family Ophiacanthidae (Echinodermata: Ophiuroidea). European Journal of Taxonomy 48: 1-242, DOI: 10.5852/ejt.2013.48
Classification
- kingdom
- Animalia
- phylum
- Echinodermata
- class
- Ophiuroidea
- order
- Ophiurida
- family
- Ophiomyxidae
- genus
- Ophiologimus
- species
- Ophiologimus aiodipius
description
Description Holotype GZG. INV. 78536 is a dissociated, large, proximal LAP; slightly wider than high; dorsal edge straight; distal edge convex; proximal edge concave, devoid of spurs; ventral fifth of LAP strongly protruding ventro-proximalwards; ventro-distal tip of LAP slightly protruding; outer surface with coarsely meshed stereom; trabeculae merging into short, irregular, vertical stripes close to spine articulations; coarsely meshed stereom replaced by finely meshed stereom in narrow band along proximal edge of LAP. Four large, lenticular, oblique, slightly elongate, nearly equal-sized and equidistant spine articulations freestanding on non-elevated distal portion of LAP; dorsal and ventral lobes merged by sharp, acute kink proximally into continuous volute; gap between spine articulations and distal edge of LAP narrow, slightly increasing in width ventralwards. Ventral edge of LAP with very large, moderately deeply incised, concave tentacle notch. Inner side of LAP with large, very slender ridge; dorsal part of ridge straight, oblique; ventral part almost vertical, merged with ventral portion of LAP and connected with dorsal part by gently rounded kink; no spurs on inner side of distal edge of LAP; inner side of tentacle notch very large. No perforations or furrow discernible. Paratype supplements and variation GZG. INV. 78537 is a dissociated distal LAP; approximately twice wider than high; well in agreement with holotype; outer surface with very coarsely meshed stereom; trabeculae merged into shorter and even less regular vertical stripes than in holotype. Three spine articulations similar to those observed in holotype but with dorsalward increase in size. Ventral edge of LAP with very large, but shallow tentacle notch. Ridge on inner side of LAP straight, oblique, slender, merged ventrally with ventral portion of LAP.
description
urn: lsid: zoobank. org: act: C 014 CC 2 C- 60 E 3 - 43 F 6 - B 1 D 6 - 20 F 6410 E 6 A 97 Fig. 11: 5 - 6
diagnosis
Diagnosis Species of Ophiologimus with large LAPs displaying coarsely meshed stereom on outer surface; trabeculae of coarsely meshed stereom merged into short, irregular vertical stripes close to spine articulations; up to four lenticular, oblique spine articulations; ridge on inner side of LAPs very slender; ventral part of ridge merged with ventral portion of LAP and connected with dorsal part of ridge by gently rounded kink; tentacle notch rather shallow.
discussion
Remarks These LAPs are unambiguously assignable to Ophiologimus on account of the very large tentacle notch combined with the spine articulations freestanding on the non-elevated distal portion of the LAP and the simple ridge on the inner side devoid of conspicuously thickened parts. Among the fossil LAP types assigned to this genus, the above is unique in combining a coarsely meshed outer surface stereom with lenticular, oblique spine articulations and a continuous ridge on the inner side with the ventral part merged with the ventral portion of the LAP. Occurrence Latest Aptian to earliest Albian of the tropical northeast Atlantic.
distribution
Type locality and horizon Blake Nose, borehole ODP 171 B 1049 C 12 x 5, tropical northeast Atlantic; latest Aptian to earliest Albian, Hedbergella trochoidea to Microhedbergella rischi planktonic foraminifer zones, Early Cretaceous.
etymology
Etymology Species name derived from IODP, Integrated Ocean Drilling Program, under which the samples yielding the type material were recovered.
materials_examined
Additional material GZG. INV. 78538 (33 dissociated LAPs).
materials_examined
Type material Holotype GZG. INV. 78536. Paratypes GZG. INV. 78537.
Name
- Homonyms
- Ophiologimus aiodipius Thuy 2013