Abstract

AbstractThe Sirius Passet Lagerstätte of North Greenland is one of the oldest records of soft‐bodied metazoan‐dominated ecosystems from the early Cambrian. The Lagerstätte site itself is restricted to just a singlec. 1‐km‐long outcrop located offshore from the shelf margin, in an area affected by metamorphic alteration during the Ellesmerian Orogeny (Devonian – Early Carboniferous). The recent recovery of small carbonaceous fossils (SCFs) to the south, in areas that escaped the effects of this deformation, has substantially expanded the known coverage of organic preservation into shallower water depositional settings in this region. Here, we describe additionalSCFassemblages from the siliciclastic shelf succession of the Buen Formation (Cambrian Series 2, stages 3–4;c. 515 Ma), expanding the previously documentedSCFbiota. Newly recovered material indicates a rich diversity of non‐mineralizing metazoans, chiefly represented by arthropod remains. These include the filtering and grinding elements of a sophisticated crustacean feeding apparatus (the oldest crustacean remains reported to date), alongside an assortment of bradoriid sclerites, including almost complete, 3D valves, which tie together a number ofSCFs previously found in isolation. Other metazoan remains include various trilobite cuticles, diverse scalidophoran sclerites, and a range of metazoan fragments of uncertain affinity. This shallower water assemblage differs substantially from the Sirius Passet biota, which is dominated by problematic euarthropod stem‐group members and sponges. Although some of these discrepancies are attributable to taphonomic or temporal factors, these lateral variations in taxonomic composition also point to significant palaeoenvironmental and/or palaeoecological controls on early Cambrian metazoan communities.

Highlights

  • (the oldest crustacean remains reported to date), alongside an assortment of bradoriid sclerites, including almost complete, 3D valves, which tie together a number of small carbonaceous fossils (SCFs) previously found in isolation

  • The known outcrop area of the Burgess Shale and Chengjiang deposits has been continuously expanded, comparatively little is known of the spatial variation in faunas surrounding another major Cambrian Lagerst€atte; the Sirius Passet biota from North Greenland

  • Both nevadiid and olenellid trilobites occur in Brillesø locality 1 (B1, Fig. 1D), which has tentatively been correlated with the uppermost part of the Nevadella Zone, corresponding to the Nevadia addyensis trilobite Zone of the Montezuman Stage (Cambrian Stage 3; Hollingsworth 2011; Peel & Willman 2018)

Read more

Summary

Introduction

(the oldest crustacean remains reported to date), alongside an assortment of bradoriid sclerites, including almost complete, 3D valves, which tie together a number of SCFs previously found in isolation. Other metazoan remains include various trilobite cuticles, diverse scalidophoran sclerites, and a range of metazoan fragments of uncertain affinity This shallower water assemblage differs substantially from the Sirius Passet biota, which is dominated by problematic euarthropod stem-group members and sponges. The known outcrop area of the Burgess Shale and Chengjiang deposits has been continuously expanded, comparatively little is known of the spatial variation in faunas surrounding another major Cambrian Lagerst€atte; the Sirius Passet biota from North Greenland Another means of capturing some of this spatial (and palaeoenvironmental) diversity is offered by the record of small carbonaceous fossils (SCFs). These relatively relaxed constraints on soft-tissue fossilization significantly expanded the spatial and temporal range of a number of otherwise poorly preserved clades, such as planktonic crustaceans (Butterfield 1994; Harvey et al 2012), wiwaxiids (Harvey et al 2011; Butterfield & Harvey 2012) and annelids (Slater et al 2017; Slater & Willman 2019)

Methods
Discussion
Conclusion

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 call

Disclaimer: 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.