Phylogenetic position and stratigraphic uncertainty of a new flexible crinoid from the Ordovician–Silurian boundary of Anticosti Island (Québec, Canada)

Researchers have identified a new flexible crinoid species, Anticosticrinus natiscotecensis, from the Ordovician–Silurian boundary of Anticosti Island (Québec, Canada), a region critical for studying the Late Ordovician mass extinction (LOME). Phylogenetic analysis places this species within the family Anisocrinidae, contributing to understanding crinoid faunal turnover during this pivotal period. The study also employed Bayesian methods to quantify stratigraphic age uncertainty, suggesting a late Hirnantian age, though not definitively resolving it. This discovery provides valuable data for evaluating extinction timing and diversification patterns in flexible crinoids, which became dominant in the Silurian.

Cole, S. R., Wright, D. F., & Hopkins, M. J. (2025). Phylogenetic position and stratigraphic uncertainty of a new flexible crinoid from the Ordovician–Silurian boundary of Anticosti Island (Québec, Canada). Journal of Paleontology, 99(2), 358–368. https://doi.org/10.1017/jpa.2025.10110