Fossil crinoids from Panthalassa

PUBLICATION — Salamon, M.A., Brachaniec, T., Bressan, G.S., Ciesielczuk, J., Esquivel-Macias, C., Gaidzik, K., Kapitany, T., Klompmaker, A.A., Krajewski, M., Lazo, D.G., Oji, T., Poatskievick-Pierezan, B., Płachno, B.J., Rubilar Rodriguez, A., Wilk, A., Humański, K., Gorzelak, P., 2026, Delayed deepening: Bathymetric patterns of post-Paleozoic stalked crinoids in the Panthalassan realm. Geology. https://doi.org/10.1130/G54806.1

Figure: Crown of an Oligocene crinoid from Oregon.

Today, stalked crinoids are confined to the deep sea, although their ancestors once dominated shallow-marine environments. Our analysis of the fossil record from the ancient Panthalassa Ocean shows that their restriction to deep-water habitats occurred much later than in the Tethyan realm. These findings indicate that marine ecosystem restructuring proceeded at different rates across the globe, challenging the idea of a globally synchronous impact of the so-called Mesozoic Marine Revolution.