Open Paleo

Talos

Zanno et al., 2011 TAY-luhs /ˈteɪlɒs/

Named after Talos, the bronze giant automaton of Greek mythology who protected the island of Crete, referencing the raptor's taloned foot.

83.6–72.2 million years ago Campanian, Late Cretaceous
Late Cretaceous stages

Talos is a genus of troodontid theropod dinosaur from the Late Cretaceous Kaiparowits Formation of Utah, United States. It contains a single species, Talos sampsoni, described from a partial skeleton in 2011. Talos was a small bipedal carnivore approximately 2 m long.

Under dispute

Talos is a North American troodontine whose finer position is contested: it is recovered among the derived troodontines by some analyses (Hartman and colleagues, 2019) and in a more basal troodontine position by others (Averianov and Sues, 2016; van der Reest and Currie, 2017). It is placed in Troodontinae.

Diagnosis

  1. Intercondylar bridge of astragalus hyperconstricted
  2. Proximal groove separating astragalar body and ascending process craniocaudally wide and V-shaped
  3. Shaft of metatarsal II markedly compressed with midshaft length-to-transverse width ratio of 38.8
  4. Pronounced, rounded tab on dorsolateral aspect of metatarsal III proximal to distal condyle
  5. Distal corner of lateral collateral ligament pit on metatarsal IV with small protuberance creating rounded depression between extensor aspects of distal condyles

Species

Talos sampsoni Zanno et al., 2011

Type species

Named in honor of Dr. Scott D. Sampson for researching and collecting fossils during the Kaiparowits Basin Project.

Holotype
UMNH VP 19479 , Utah Museum of Natural History
Material
Partial postcranial skeleton including fragmentary portions of dorsal, sacral, and caudal axial column, left ulna, forelimb fragments, partial pelvis, and partial left and right hind limbs
Horizon
middle Kaiparowits Formation, Campanian, Late Cretaceous , 83.6–72.2 million years ago
Locality
The Blues, Utah, United States

References

  1. Zanno, L. E.; Varricchio, D. J.; O'Connor, P. M.; Titus, A. L.; Knell, M. J. (2011). A New Troodontid Theropod, Talos sampsoni gen. et sp. nov., from the Upper Cretaceous Western Interior Basin of North America. PLoS ONE 6(9): e24487. Public Library of Science (PLoS). doi:10.1371/journal.pone.0024487 zanno2011a
  2. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Theropods. Princeton University Press.

    Source of the hip height estimate, and the appearance features.

    jones2026c
  3. Hartman, S.; Mortimer, M.; Wahl, W. R.; Lomax, D. R.; Lippincott, J.; Lovelace, D. M. (2019). A new paravian dinosaur from the Late Jurassic of North America supports a late acquisition of avian flight. PeerJ 7: e7247. PeerJ. doi:10.7717/peerj.7247

    Recovered Talos among derived troodontines.

    hartman2019a
  4. van der Reest, A. J.; Currie, P. J. (2017). Troodontids (Theropoda) from the Dinosaur Park Formation, Alberta, with a description of a unique new taxon: implications for deinonychosaur diversity in North America. Canadian Journal of Earth Sciences 54(9): 919-935. doi:10.1139/cjes-2017-0031

    Recovered Talos in a more basal troodontine position, contrasting with a derived placement in other studies.

    vanderreest2017a
  5. Averianov, A. O.; Sues, H. D. (2016). Troodontidae (Dinosauria: Theropoda) from the Upper Cretaceous of Uzbekistan. Cretaceous Research 59: 98-110. Elsevier BV. doi:10.1016/j.cretres.2015.11.005

    Recovered Talos in a more basal troodontine position.

    averianov2016a