Genus
Ichnogenus Extinct

Saurexallopus

Harris 1997

Saurexallopus is an ichnogenus of four-toed theropod footprints from the Late Cretaceous period. The type ichnospecies is S. lovei, named and described in 1996 from the Harebell Formation. The taxon was originally named Exallopus, but later renamed as Saurexallopus as the former was preoccupied by a polychaete. A second species, S.zerbsti, was named and described in 2004 from the Lance Formation. In 2012 a four-toed track from the Cantwell Formation was referred to Saurexallopus indet. It was also suggested that Saurexallopus was produced by a therizinosaur taxon. In 2013 based on skeletal proportions it was suggested that the ichnotaxon was instead produced by an oviraptorosaur taxon. In 2014 a third species was named, S.cordata, from the Wapiti Formation. In 2018 several tracks from the Blackhawk Formation were referred to Saurexallopus indet. A 2026 study found the type species of the genus S.lovei as a nomen dubium as they are based on penetrative tracks

Temporal range
Triassic
Jurassic
Cretaceous
Paleogene
Neogene
252 201 145 66 0 Ma
PBDB occurrences
7
Group
Dinosaures
Omnivore Ground dwelling (surface) Terrestrial
Saurexallopus
click to enlarge
Saurexallopus, a four toed dinosaur or bird trace fossil (jr syn Exallopus © Ghedoghedo · CC BY-SA 3.0 · Wikimedia
PBDB Wikipedia
Classification
Dinosauria Unranked clade
Theropoda Unranked clade
Neotheropoda Unranked clade
Averostra Unranked clade
Tetanurae Unranked clade
Coelurosauria Unranked clade
Maniraptora Unranked clade
Oviraptorosauria Infraorder
Saurexallopus Genus
Fossil sites 7 geolocated sites
Distribution
Top countries
🇺🇸 United States
5
🇵🇱 Poland
1
🇨🇦 Canada
1
Geological formations
Harebell
2
Cantwell
1
Wapiti
1
Laramie
1
Lance
1
Temporal distribution
Maastrichtian (72.2–66 Ma)
4
Campanian (83.6–72.2 Ma)
3
Species (3)
Saurexallopus cordata 84 Ma
Saurexallopus lovei 72 Ma
Saurexallopus zerbsti 72 Ma
Synonyms (1)
Exallopus replaced by Saurexallopus
Images 1
Bibliography
Original description
J. D. Harris. 1997. Four-toed theropod footprints and a paleomagnetic age from the Whetstone Falls Member of the Harebell Formation (Upper Cretaceous: Maastrichtian), northwestern Wyoming: a correction. Cretaceous Research 18:139 DOI ↗
Bibliography (6)
M. G. Lockley, B. Simmons, and S. E. Hirschfeld. 2018. A new dinosaur track locality in the Late Cretaceous (Maastrichtian) Laramie Formation of Colorado. Fossil Record 6. New Mexico Museum of Natural History and Science Bulletin 79:395-406
G. D. Gierlinski. 2015. New dinosaur footprints from the Upper Cretaceous of Poland in the light of paleogeographic context. Ichnos 22(3–4):220-226 DOI ↗
R. T. McCrea, L. G. Buckley, and A. G. Plint, P. J. Currie, J. W. Haggart, C. W. Helm, S. G. Pemberton. 2014. A review of vertebrate track-bearing formations from the Mesozoic and earliest Cenozoic of western Canada with a description of a new theropod ichnospecies and reassignment of an avian ichnogenus. Fossil Footprints of Western North America. New Mexico Museum of Natural History and Science Bulletin 62:5-94
A. R. Fiorillo and T. L. Adams. 2012. A therizinosaur track from the Lower Cantwell Formation (Upper Cretaceous) of Denali National Park, Alaska. Palaios 27:394-400 DOI ↗
M. G. Lockley, G. Nadon, and P. J. Currie. 2003. A diverse dinosaur-bird footprint assemblage from the Lance Formation, Upper Cretaceous, eastern Wyoming; implications for ichnotaxonomy. Ichnos 11:229-249 DOI ↗
J. D. Harris, K. R. Johnson, and J. Hicks, L. Tauxe. 1996. Four-toed theropod footprints and a paleomagnetic age from the Whetstone Falls Member of the Harebell Formation (Upper Cretaceous: Maastrichtian), northwestern Wyoming. Cretaceous Research 17:381-401 DOI ↗