Open Paleo

Camposaurus

Hunt et al., 1998 KAMP-o-SOR-uhs /ˌkæmpoʊˈsɔːrəs, -pə-/

Named for Charles Lewis Camp, an American paleontologist, combined with Greek 'sauros' meaning 'lizard'.

237.0–205.7 million years ago Carnian–Norian, Late Triassic
Late Triassic stages

Camposaurus is a coelophysid dinosaur genus from the Norian stage of the Late Triassic period of North America. The pertinent fossil remains date back to the early to middle Norian stage, and is widely regarded as the oldest known neotheropod.

Diagnosis

  1. Tarsals fused to the tibia and fibula (shared only with Rioarribasaurus and Syntarsus among ceratosaurs)
  2. Ventral margin of astragalus in anterior/posterior view is horizontal rather than deeply concave
  3. Fibula in contact with tibia in anterior view for a distance equal to at least one and a half times the width of the astragalus plus calcaneum
  4. Femoral head more rectangular than in Coelophysis and Syntarsus
  5. Dorsal centra more waisted in ventral view than in Coelophysis and Syntarsus

Species

Camposaurus arizonensis Hunt et al., 1998

Type species

Named for Arizona, the US state where the holotype was discovered.

Holotype
UCMP 34498 , University of California Museum of Paleontology
Material
Associated right and left distal hindlimbs and fused astragali and calcanea (fused right tibia/fibula/astragalus/calcaneum)
Horizon
Mesa Redondo Member, Chinle Formation, Carnian–Norian, Late Triassic , 237.0–205.7 million years ago
Locality
Placerias Quarry, Arizona, United States Hunt and colleagues (1998) place the taxon in the Adamanian, which they call late Tuvalian (late Carnian); Novas and colleagues (2021) date the Placerias Quarry to about 219 Ma, which is Norian.

References

  1. Novas, F. E.; Agnolín, F. L.; Ezcurra, M. D.; Müller, R. T.; Martinelli, A. G.; Langer, M. C. (2021). Review of the fossil record of early dinosaurs from South America, and its phylogenetic implications. Journal of South American Earth Sciences 110: 103341. doi:10.1016/j.jsames.2021.103341

    Gives the Placerias Quarry as "ca. 219 Ma".

    novas2021a
  2. Hunt, A. P.; Lucas, S. G.; Heckert, A. B.; Sullivan, R. M.; Lockley, M. G. (1998). Late Triassic dinosaurs from the western United States. Geobios 31(4): 511-531. Elsevier BV. doi:10.1016/s0016-6995(98)80123-x hunt1998a