The Souss lagerst\xe4tte of the Anti-Atlas, Morocco: discovery of the first Cambrian fossil lagerst\xe4tte from Africa

Ed Landing,Gerd Geyer

doi:10.1038/s41598-021-82546-0

Abstract

Episodic low oxygenated conditions on the sea-floor are likely responsible for exceptional preservation of animal remains in the upper Amouslek Formation (lower Cambrian, Stage 3) on the northern slope of the western Anti-Atlas, Morocco. This stratigraphic interval has yielded trilobite, brachiopod, and hyolith fossils with preserved soft parts, including some of the oldest known trilobite guts. The “Souss fossil lagerstätte” (newly proposed designation) represents the first Cambrian fossil lagerstätte in Cambrian strata known from Africa and is one of the oldest trilobite-bearing fossil lagerstätten on Earth. Inter-regional correlation of the Souss fossil lagerstätte in West Gondwana suggests its development during an interval of high eustatic levels recorded by dark shales that occur in informal upper Cambrian Series 2 in Siberia, South China, and East Gondwana.

Highlights

Episodic low oxygenated conditions on the sea-floor are likely responsible for exceptional preservation of animal remains in the upper Amouslek Formation on the northern slope of the western Anti-Atlas, Morocco
During the century that passed since Walcott’s discovery of the Burgess Shale, macroscopic, exceptionally preserved fossil assemblages have been discovered on all major Cambrian palaeocontinents, and more than 30 genera of non-biomineralizing organisms have been discovered from the Marjum Formation alone
Exceptional preservation in the Cambrian strata of Morocco was previously unknown except for a single xandarellid specimen found in the uppermost lower Cambrian strata in the High Atlas that reflects singular local obrutional p reservation[23] which did not regularly affect any of the other fossils frequently found in these strata

Summary

Introduction

Episodic low oxygenated conditions on the sea-floor are likely responsible for exceptional preservation of animal remains in the upper Amouslek Formation (lower Cambrian, Stage 3) on the northern slope of the western Anti-Atlas, Morocco. New data convincingly indicate the presence of a fossil lagerstätte in the Cambrian Stage 3 Amouslek Formation of the western Anti-Atlas, Morocco.

Results

Conclusion