| Zusammenfassung: | The Manning Canyon Shale Formation (upper Mississippian/lower Pennsylvanian) of Central Utah is well known for its diverse flora, but not its vertebrate fauna. The previously described vertebrates from the Manning Canyon Shale are a tooth from a cladodont shark, an acanthodian, and a microsaur. Here, the known vertebrate diversity is expanded with the description of early actinopterygian fishes. The actinopterygian ichthyofauna consists of two new species of 'palaeoniscoid' fishes, Spinofacia pectinatus and Guntherichthys lehiensis, and a new aeduellid species, Bourbonnella jocelynae. Spinofacia pectinatus is characterized by the presence of extra lateral gulars (the only documented case outside the Bear Gulch Limestone of Montana) and extra-oral denticles on various dermal bones of the skull, whereas Guntherichthys lehiensis is distinguished by scales with slightly rounded posterior margins. The new aeduellid, Bourbonnella jocelynae, is now the earliest known aeduellid and the second occurrence of this genus and family in North America. Its discovery supports biogeographical and paleoecological findings of a marine connection between North America and Europe. The previously proposed freshwater paleoenvironment of the Manning Canyon Shale Formation is called into question, especially when the ichthyofauna of the site is considered. It is also important to note that although not many actinopterygian specimens have been collected from the Manning Canyon Shale, those that have reveal a previously unknown diversity.
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