Tyrannomimus

Tyrannomimus Temporal range: Early Cretaceous, Aptian PreꞒ Ꞓ O S D C P T J K Pg N
Diagram of known fossil material
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Dinosauria
Clade:	Saurischia
Clade:	Theropoda
Clade:	† Ornithomimosauria
Family:	† Deinocheiridae
Genus:	† Tyrannomimus Hattori et al., 2023
Species:	†T. fukuiensis
Binomial name
†Tyrannomimus fukuiensis Hattori et al., 2023

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]

Discovery and naming

Known fossil elements

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. ^[1]

Classification

Life restoration

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: ^[1]

Ornithomimosauria	Nqwebasaurus Pelecanimimus Shenzhousaurus Beishanlong LH-02-01 Deinocheiridae Tyrannomimus Harpymimus Garudimimus Deinocheirus Paraxenisaurus Ornithomimidae Archaeornithomimus Dzharacursor Sinornithomimus Rativates Struthiomimus Gallimimus Anserimimus Ornithomimus Qiupalong

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. ^[1]

Paleoenvironment

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]}

References

1. Hattori, S.; Shibata, M.; Kawabe, S.; Imai, T.; Nishi, H.; Azuma, Y. (2023). "New theropod dinosaur from the Lower Cretaceous of Japan provides critical implications for the early evolution of ornithomimosaurs". Scientific Reports. 13. 13842. doi: 10.1038/s41598-023-40804-3 . PMC   10484975 .
2. Azuma, Y.; Shibata, M. (2010). "Fukuititan nipponensis, a new titanosauriform sauropod from the Early Cretaceous Tetori Group of Fukui Prefecture, Japan". Acta Geologica Sinica - English Edition. 84 (3): 454–462. doi:10.1111/j.1755-6724.2010.00268.x.
3. Shibaba, Masateru; Azuma, Yoichi (2015). "New basal hadrosauroid (Dinosauria: Ornithopoda) from the Lower Cretaceous Kitadani Formation, Fukui, central Japan" (PDF). Zootaxa. 3914 (4): 421–440. doi:10.11646/zootaxa.3914.4.3. PMID   25661952.|
4. Imai, T., Azuma, Y., Kawabe, S., Shibata, M., Miyata, K., Wang, M., & Zhou, Z. (2019). An unusual bird (Theropoda, Avialae) from the Early Cretaceous of Japan suggests complex evolutionary history of basal birds. Communications Biology, 2(1). doi: 10.1038/s42003-019-0639-4