TY - JOUR TI - A Permian fish reveals widespread distribution of neopterygian-like jaw suspension AU - Argyriou, Thodoris AU - Giles, Sam AU - Friedman, Matt A2 - Zhu, Min A2 - Perry, George H A2 - Zhu, Min A2 - Ahlberg, Per E VL - 11 PY - 2022 DA - 2022/05/17 SP - e58433 C1 - eLife 2022;11:e58433 DO - 10.7554/eLife.58433 UR - https://doi.org/10.7554/eLife.58433 AB - The actinopterygian crown group (comprising all living ray-finned fishes) originated by the end of the Carboniferous. However, most late Paleozoic taxa are stem actinopterygians, and broadly resemble stratigraphically older taxa. The early Permian †Brachydegma caelatum is notable for its three-dimensional preservation and past phylogenetic interpretations as a nested member of the neopterygian crown. Here, we use computed microtomography to redescribe †Brachydegma, uncovering an unanticipated combination of primitive (e.g., aortic canal; immobile maxilla) and derived (e.g., differentiated occipital ossifications; posterior stem of parasphenoid; two accessory hyoidean ossifications; double jaw joint) dermal and endoskeletal traits relative to most other Paleozoic actinopterygians. Some of these features were previously thought to be restricted to the neopterygian crown. The precise phylogenetic position of †Brachydegma is unclear, with placements either on the polypterid stem or as an early-diverging stem neopterygian. However, our analyses decisively reject previous placements of †Brachydegma in the neopterygian crown. Critically, we demonstrate that key endoskeletal components of the hyoid portion of the suspensorium of crown neopterygians appeared deeper in the tree than previously thought. KW - Actinopterygii KW - paleozoic KW - Brachydegma KW - hyoid arch KW - phylogeny KW - double jaw joint JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -