Abstract
Abstract Ophiuroids, the slender-armed cousins of starfish, constitute an important component of modern marine benthos and have been used successfully in the exploration of (palaeo)-ecological and evolutionary trends, yet their fossil record is still poorly known. One of the major gaps in the known palaeobiodiversity of this group coincides with a global palaeoenvironmental crisis during the early Toarcian (Early Jurassic, 183 myr ago), known as the Jenkyns Event. Here we describe ophiuroid remains retrieved from a series of samples from the Dudelange (Luxembourg) drill core, which spans the lower part of the Toarcian, between the top of the Pliensbachian and the onset of the Jenkyns Event. A total of 21 species are recorded, including three new genera and 12 new species. Ophiuroid diversity and abundance fluctuate in parallel with depositional facies, with lowest values coinciding with black shales. Highest diversities, including exceptional occurrences of taxa nowadays restricted to deep-sea areas, are recorded from just below the black shales, corresponding to the onset of the Jenkyns Event. Our results show that even small (100 g) bulk sediment samples retrieved from drill cores can yield numerous identifiable ophiuroid remains, thus unlocking this group for the study of faunal change across palaeoenvironmental crises.
Highlights
Brittlestar diversity at the dawn of the Jenkyns Event: new microfossils from the Dudelange drill core, Luxembourg
We describe ophiuroid remains retrieved from a series of samples from the Dudelange (Luxembourg) drill core, which spans the lower part of the Toarcian, between the top of the Pliensbachian to the
P corresponding to the onset of the Jenkyns Event
Summary
Enakomusium geisingense (Kutscher, 1992) from Bachhausen, and Sinosura brodiei (Wright, 1866) from Ohmden (Hess 1991). Both records, lack a more precise stratigraphic. PT Here, we describe ophiuroid microfossils from a series of bulk sediment samples taken from the E basal Toarcian interval of the Dudelange drill core. The material represents 35 stratigraphically successive assemblages comprising a total of 21 species, adding significantly to the Toarcian. In C addition to an exhaustive taxonomic assessment of the assemblages, we explore species range and A diversity patterns across the sampled interval and investigate potential palaeobiological implications
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
