Overview
- The species, Sonselasuchus cedrus, comes from the Sonsela Member of Arizona’s Chinle Formation and belongs to croc-line shuvosaurids/poposauroids.
- More than 3,000 fossils have been recovered from the site since 2014, including about 950 bones assigned to the new taxon.
- Analyses show forelimbs grew on a negative allometric trajectory relative to hind limbs, supporting an ontogenetic shift toward adult bipedalism.
- The animal was roughly 25 inches tall and likely bore a toothless beak, large eye sockets, and hollow bones, features that recall ornithomimid dinosaurs.
- The authors interpret those similarities as convergent evolution, with croc-line and bird-line archosaurs filling comparable ecological roles in Late Triassic ecosystems.