Manfredura, Thuy, 2013

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, pp. 1-242 : 196-197

Genus Manfredura gen. nov.

urn:lsid:zoobank.org:act:48A7EB27-E847-4C00-A732-8D8EAC80227B

Type and sole known species

Ophiomyxa? curvata Kutscher & Jagt, 2000 .

Diagnosis

Ophiuroid with large, conspicuously thick and strongly curved LAPs; proximal LAPs several times higher than wide; numerous non-oblique, ear-shaped spine articulations freestanding on strongly elevated distal portion of LAPs; inner side of LAP with very small, slender ridge; LAPs of neighbouring arm segments originally in contact as evidenced by strongly depressed, narrow band along most of the proximal edge.

Etymology

Genus named in honour of Manfred Kutscher, for his generous support and indefatigable, long-standing research on the echinoderms of the Rügen Chalk, which yielded the type material of the only known species of the genus; from oura, Greek for “tail”, a commonly used suffix in ophiuroid names; gender feminine.

Remarks

Kutscher&Jagt (2000) described a highly distinctive type of dissociated LAPs from the early Maastrichtian of Germany and Denmark as Ophiomyxa ? curvata . A reassessment of the type material has revealed that these LAPs display large ear-shaped spine articulations with a well-developed sigmoidal fold. Along with the general morphology, the spine articulation structure precludes assignment to the Ophiomyxidae Ljungman, 1867 but rather places this LAP type in the Ophiacanthidae . Within this family, however, affinities are more problematic. Similarly curved, thick and massive LAPs devoid of outer surface ornament are found only in Ophioleviathan gen. nov. and, to a lesser extent, Inexpectacantha . The LAPs of these two, however, display fundamentally different spine articulations, and the ridge on the inner side of the LAPs is much larger. Superficial similarities are shared with the LAPs of extant Ophientrema Verrill, 1899 , in particular on account of the extremely large height/width ratio, the strong curvature and the lack of outer surface ornament. However, while these two genera are characterised by a large uncalcified gap between the LAPs of neighbouring arm segments, the LAPs known as Ophiomyxa ? curvata display a strongly depressed, narrow band along most of the proximal edge, suggesting that the LAPs were in contact or even slightly overlapped. In addition, the LAPs of Ophiomyxa ? curvata display a much shorter, tongue-shaped ridge.

These LAPs cannot be reconciled convincingly with the LAP morphological diagnosis of any currently known ophiacanthid. It thus seems best to introduce Manfredura gen. nov. to accommodate them. The similarities in general LAP morphology, the small, poorly defined tentacle notch and the considerably smaller but similarly shaped ridge on the inner side, suggests that Manfredura gen. nov. is closest to Ophioleviathan gen. nov. and Inexpectacantha . It seems unlikely, however, that it belongs to the same lineage, considering the fundamental differences in spine articulation morphology. At the present state of knowledge, the phylogenetic position of Manfredura gen. nov. within the small-pored ophiacanthids remains elusive.