A spectacular site in France is a rare window into the lower Ordovician
biota.

https://www.nature.com/articles/s41559-024-02331-w

The Cabrières Biota (France) provides insights into Ordovician polar
ecosystems

Abstract

Early Palaeozoic sites with soft-tissue preservation are predominantly
found in Cambrian rocks and tend to capture past tropical and temperate
ecosystems. In this study, we describe the diversity and preservation of
the Cabrières Biota, a newly discovered Early Ordovician Lagerstätte
from Montagne Noire, southern France. The Cabrières Biota showcases a
diverse polar assemblage of both biomineralized and soft-bodied
organisms predominantly preserved in iron oxides. Echinoderms are
extremely scarce, while sponges and algae are abundantly represented.
Non-biomineralized arthropod fragments are also preserved, along with
faunal elements reminiscent of Cambrian Burgess Shale-type ecosystems,
such as armoured lobopodians. The taxonomic diversity observed in the
Cabrières Biota mixes Early Ordovician Lagerstätten taxa with Cambrian
forms. By potentially being the closest Lagerstätte to the South Pole,
the Cabrières Biota probably served as a biotic refuge amid the
high-water temperatures of the Early Ordovician, and shows comparable
ecological structuring to modern polar communities.