Tyrannomimus (meaning "tyrant mimic") is an extinct genus of ornithomimosaurian theropod dinosaurs from the Kitadani Formation of Japan. The type species is Tyrannomimus fukuiensis.[1]
Tyrannomimus is based on the holotype FPDM-V-11311, a partial postrcranial skeleton. Multiple referred specimens are also known.
They were named as a new genus and species of ornithomimosaur in 2023. The generic name, "Tyrannomimus", is a reference to its morphological similarities with tyrannosauroids, particularly the vertical ridge of the ilium previously believed to be a synapomorphy of that clade and shared with Aviatyrannis. The specific name, "fukuiensis", refers to Fukui Prefecture where the fossils were found.
Tyrannomimus was entered in a phylogenetic analysis by Hattori et al. (2023) and placed within the family Deinocheiridae, as the sister taxon to Harpymimus. Their cladogram is shown below:
Although it wasn't included in the dataset, Hattori et al. also consider Aviatyrannis to be a basal ornithomimosaur due to its similarities with Tyrannomimus.
Tyrannomimus lived alongside a diverse assemblage of animals, most of which are named after Fukui Prefecture. These include the sauropod Fukuititan, the ornithopods Fukuisaurus and Koshisaurus, and the theropods Fukuiraptor, Fukuivenator, and Fukuipteryx.[2] [3] [4]