Open Paleo

Saurornitholestes

Sues, 1978 SAWR-or-NITH-o-LES-teez

From Greek sauros (lizard), ornithos (bird), and lestes (thief); meaning "lizard-bird thief".

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

Saurornitholestes is a genus of carnivorous dromaeosaurid theropod dinosaur from the late Cretaceous of Canada (Alberta and Saskatchewan) and the United States (Montana, New Mexico, Alabama, and South Carolina). Two species have been named that are regarded as valid: Saurornitholestes langstoni in 1978 and Saurornitholestes sullivani in 2015. Saurornitholestes was a small, bipedal, meat-eating dinosaur, equipped with a sickle-like claw on each foot.

Diagnosis

  1. Very small, lightly built theropod with frontal triangular and not basined between median suture and orbital rim
  2. Posterior frontal well-rounded and slightly inflated, without frontoparietal crest
  3. Lateral walls of anterior endocranial cavity flaring laterally
  4. Ectopterygoid complex with ventral pocket
  5. Teeth with well-developed denticles (24-26 per 5mm) on posterior carinae and tiny denticles (c.35 per 5mm) on anterior carinae

Species (2)

Saurornitholestes langstoni Sues, 1978

Type species

Named for Wann Langston, Jr., a prominent Canadian paleontologist.

Holotype
TMP 1974.010.0005 , Royal Tyrrell Museum of Paleontology
Formerly
PMAA P74.10.5 (rehoused from Provincial Museum and Archives of Alberta)
Material
Associated remains of incomplete skeleton including both frontals, left ectopterygoid, left quadrate, two teeth, two vertebrae, gastralia, rib fragments, metacarpal, phalanges and unguals of left manus.
Horizon
Dinosaur Park Formation, Campanian, Late Cretaceous , 83.6–72.2 million years ago
Locality
Quarry 140, Alberta, Canada

Saurornitholestes sullivani Jasinski, 2015

Honors Robert M. Sullivan, who discovered the holotype and whose work advanced study of the Late Cretaceous San Juan Basin.

Holotype
SMP VP-1270 , State Museum of Pennsylvania
Material
A nearly complete, slightly water-worn left frontal
Horizon
De-na-zin Member, Kirtland Formation, Campanian, Late Cretaceous , 83.6–72.2 million years ago
Locality
Hunter Wash (SMP locality 311), New Mexico, United States
Diagnosis
  1. Frontal more constricted anteriorly
  2. Orbital rim deeper and less strongly demarcated
  3. Olfactory bulb surface deeper and more prominent
  4. Ridge between the olfactory bulb and cerebral hemisphere surfaces more pronounced and longer ventrally
  5. Frontal-frontal sutural surface more robust
  6. Frontal slightly smaller overall yet more robust

References

  1. Sues, H. D. (1978). A new small theropod dinosaur from the Judith River Formation (Campanian) of Alberta Canada. Zoological Journal of the Linnean Society 62(4): 381-400. Oxford University Press (OUP). doi:10.1111/j.1096-3642.1978.tb01049.x

    Gives the type horizon as the "Judith River Formation (Campanian), Dinosaur Provincial Park"; the Maastrichtian records of the species rest on referred teeth, not the holotype.

    sues1978a
  2. Paul, G. S. (2024). The Princeton Field Guide to Predatory Dinosaurs. Princeton University Press.

    Source of the appearance features.

    paul2024b
  3. Jasinski, S. E. (2015). A new dromaeosaurid (Theropoda: Dromaeosauridae) from the Late Cretaceous of New Mexico. New Mexico Museum of Natural History and Science Bulletin 67: 79-88. New Mexico Museum of Natural History and Science. jasinski2015a