Open Paleo

Abydosaurus

Chure et al., 2010 ah-BEE-do-SOR-us

Named after Abydos, an ancient city, combined with Greek 'sauros' meaning 'lizard'; meaning 'Abydos lizard'

113.2–100.5 million years ago Albian, Early Cretaceous
Early Cretaceous stages

Abydosaurus is a genus of brachiosaurid sauropod dinosaur known from skull and postcranial material found in upper Lower Cretaceous rocks of northeastern Utah, United States.

Diagnosis

  1. Nasal lateral process directed anteriorly and lacking a posterior hook
  2. Maxilla narial process with dorsal articulation for the nasal
  3. Nasals overlap asymmetrically on the midline
  4. External nares smaller than the orbit
  5. Upper tooth shafts twist through an arc of nearly 45 degrees
  6. Tooth wear present only mesially

Species

Abydosaurus mcintoshi Chure et al., 2010

Type species

Named for John S. ('Jack') McIntosh, Professor of Physics Emeritus at Wesleyan University, for contributions to Dinosaur National Monument and the study of sauropod dinosaurs.

Holotype
DINO 16488 , Dinosaur National Monument
Material
Nearly complete, articulated skull and lower jaws preserved in articulation with the first four cervical vertebrae
Horizon
Cedar Mountain Formation, Albian, Early Cretaceous , 113.2–100.5 million years ago
Locality
DNM 16, Utah, United States Chure and colleagues (2010) place the bone bed "near the base of the Mussentuchit Member" and date it by zircon to "no older than the mid-Albian", with the Cenomanian Dakota Formation above. Sprinkel and colleagues (2012) hold that the Mussentuchit name "should not be applied to the uppermost part of the Cedar Mountain Formation in northeastern Utah", the Mussentuchit of central Utah being "time equivalent to the Mowry Shale in northeast Utah", and date a bentonite in the overlying Dakota there at 101.4 Ma, late Albian on the ICS chart v2024/12.

References

  1. Chure, D.; Britt, B. B.; Whitlock, J. A.; Wilson, J. A. (2010). First complete sauropod dinosaur skull from the Cretaceous of the Americas and the evolution of sauropod dentition. Naturwissenschaften 97(4): 379-391. Springer Science and Business Media LLC. doi:10.1007/s00114-010-0650-6 chure2010a
  2. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Sauropods. Princeton University Press.

    Source of the mass and hip height estimates.

    jones2026b
  3. Sprinkel, D. A.; Madsen, S. K.; Kirkland, J. I.; Waanders, G. L.; Hunt, G. J. (2012). Cedar Mountain and Dakota Formations around Dinosaur National Monument—evidence of the first incursion of the Cretaceous Western Interior Seaway into Utah. Utah Geological Survey Special Study 143: 1-21.

    Limits the Mussentuchit Member to central Utah and dates a bentonite in the overlying Dakota of northeastern Utah at 101.4 Ma.

    sprinkel2012a