The Cabrières Biota (France) represents a uniquely diverse Early Ordovician ecosystem situated within the polar circle. Upon its discovery, several fossils, interpreted as algae, cnidarians, sponges, and vermiform organisms, were met with scepticism, with some researchers suggesting they were trace fossils. Subsequent studies have now clarified these interpretations. Although the Landeyran Formation, which hosts the biota, contains abundant trace fossils, these are clearly distinct from the body fossils. New descriptions have confirmed the presence of hexactinellid sponges, multiple vermiform organisms, two cnidarian taxa, and a dominance of vendotaenid-type macroalgae, effectively refuting earlier claims of misidentification. Detailed analyses of arthropods revealed a new taxon and numerous freshly moulted trilobite remains, emphasizing the exceptional preservation of this assemblage. Biomineralized organisms are also remarkably well-preserved, with echinoderms retaining fully articulated skeletons, and brachiopods, molluscs, and trilobites further refining the known fauna. Graptolite and acritarch studies constrain the age of the Cabrières Biota to the early late Floian (Fl3). Sedimentological and ichnological evidence indicates that this community inhabited a wave-influenced deltaic environment, with fossils mainly preserved in distal, environmentally stressed settings that promoted silicification, pyritization, and carbonaceous preservation. The growing understanding of this remarkable ecosystem builds on centuries of geological work in the region and reflects the combined efforts of amateur geologists, early-career researchers, and established scientists, highlighting the importance of collaborative approaches in geological discovery.
Saleh et al. (Mon,) studied this question.