A microscopic Burgess Shale: small carbonaceous fossils from a deeper water biota and the distribution of Cambrian non-mineralized faunas DOI Creative Commons
Giovanni Mussini, Nicholas J. Butterfield

Proceedings of the Royal Society B Biological Sciences, Journal Year: 2025, Volume and Issue: 292(2041)

Published: Feb. 1, 2025

(SCFs) have disclosed a record of organically preserved faunas from Cambrian epeiric seas. Their phylogenetically and functionally derived components, including probable crown-group crustaceans molluscs, are absent the ‘exceptional’ palaeoenvironmental settings captured by Burgess Shale-type (BST) macrofossil biotas. This apparent segregation SCF BST-macrofossil deposits has led to contrasting hypotheses on whether their faunal differences reflect genuine ecological patterns or overriding taphonomic controls. We report new, exceptionally diverse biota Hess River Formation Northwest Territories (Canada), which occupied an offshore slope setting. The biota, hosted single shale sample, rivals Shale in its disparity bilaterian body plans, providing microfossil counterpoint regional similar deeper-water palaeoenvironments. SCFs comprise ecdysozoan spiralian sclerites, arthropod mouthparts, semi-articulated wiwaxiids, problematica pterobranchs, but no recognizable crown molluscs crustaceans. similarities between fauna classic biotas suggest significant palaeoecological overlap, robust distinct expressions. upholds existence comparatively modern communities settings, populating both assemblages sampling

Language: Английский

A peritidal Burgess‐Shale‐type fauna from the middle Cambrian of western Canada DOI Creative Commons
Giovanni Mussini, Yorick P. Veenma, Nicholas J. Butterfield

et al.

Palaeontology, Journal Year: 2025, Volume and Issue: 68(1)

Published: Jan. 1, 2025

Abstract Burgess‐Shale‐type (BST) faunas have proven critical for mapping the Cambrian assembly of animal‐dominated ecosystems, but so far only been reported from fully subaqueous deposits. Here we integrate evidence ichnofossils, sedimentary features, and small carbonaceous fossils (SCFs) middle (Late Guzhangian, Series 3) Pika Formation western Jasper National Park, Alberta (Canada) to document a unique BST fauna, occupying peritidal habitat near outer margin large epicratonic sea. Finely laminated shales with mudcracks dumbbell‐shaped Arthraria ‐type burrows denote periodically emergent, dysoxic mudflat setting. This same facies yields SCF priapulids, annelids wiwaxiids typical deeper‐marine sediments. Recovery Cirratuliformia‐like annelid chaetae further identifies likely source associated faecal pellets. These findings show that marine metazoans, including probable members crown‐group orders, ranged beyond permanently The expanded palaeoenvironmental range taxa biota denotes remarkably broad ecological tolerances, suggesting existence guild metazoan generalists able colonize at least transiently subaerial settings. Their occupation offshore ecologies may preluded more extensive colonization high‐energy, siliciclastic marginal environments.

Language: Английский

Citations

2
A microscopic Burgess Shale: small carbonaceous fossils from a deeper water biota and the distribution of Cambrian non-mineralized faunas DOI Creative Commons
Giovanni Mussini, Nicholas J. Butterfield

Proceedings of the Royal Society B Biological Sciences, Journal Year: 2025, Volume and Issue: 292(2041)

Published: Feb. 1, 2025

(SCFs) have disclosed a record of organically preserved faunas from Cambrian epeiric seas. Their phylogenetically and functionally derived components, including probable crown-group crustaceans molluscs, are absent the ‘exceptional’ palaeoenvironmental settings captured by Burgess Shale-type (BST) macrofossil biotas. This apparent segregation SCF BST-macrofossil deposits has led to contrasting hypotheses on whether their faunal differences reflect genuine ecological patterns or overriding taphonomic controls. We report new, exceptionally diverse biota Hess River Formation Northwest Territories (Canada), which occupied an offshore slope setting. The biota, hosted single shale sample, rivals Shale in its disparity bilaterian body plans, providing microfossil counterpoint regional similar deeper-water palaeoenvironments. SCFs comprise ecdysozoan spiralian sclerites, arthropod mouthparts, semi-articulated wiwaxiids, problematica pterobranchs, but no recognizable crown molluscs crustaceans. similarities between fauna classic biotas suggest significant palaeoecological overlap, robust distinct expressions. upholds existence comparatively modern communities settings, populating both assemblages sampling

Language: Английский

Citations

1