Open Paleo

Mendozasaurus

González Riga, 2003 men-DOE-suh-SOR-us

Named for Mendoza Province in Argentina where it was discovered, combined with Greek '-saurus' meaning 'lizard'.

89.8–85.7 million years ago Coniacian, Late Cretaceous
Late Cretaceous stages

Mendozasaurus is a genus of titanosaurian sauropod dinosaur. It was a member of Titanosauria, which were massive sauropods that were common on the southern landmasses during the Cretaceous. It is represented by several partial skeletons from a single locality within the Coniacian (lower Upper Cretaceous) Sierra Barrosa Formation in the south of Mendoza Province, northern Neuquén Basin, Argentina.

Diagnosis

  1. Two subtriangular infrapostzygapophyseal fossae in anterior dorsal vertebrae over neural canal
  2. Postzygapostspinal laminae in anterior dorsal vertebrae parallel to postzygapophyseal facet planes
  3. Dorsoventrally extended interzygapophyseal cavity in anterior caudal vertebrae limited by spinopostzygapophyseal and spinoprezygapophysial laminae
  4. Middle caudal vertebrae slightly procoelous with reduced posterior condyles displaced dorsally
  5. Laminar mid-posterior caudal neural spines with horizontal straight dorsal border and anterodorsal right angle
  6. Large subconic-spherical osteoderms lacking cingulum

Species

Mendozasaurus neguyelap González Riga, 2003

Type species

From the Huarpes (Millayac language) 'neguy' meaning 'first' and 'yelap' meaning 'beast', referring to the first species of dinosaur discovered in Mendoza Province.

Holotype
IANIGLA-PV 065 , Instituto Argentino de Nivologia Glaciologia y Ciencias Ambientales
Material
22 mostly articulated caudal vertebrae and two anterior chevrons
Horizon
upper Sierra Barrosa Formation, Coniacian, Late Cretaceous , 89.8–85.7 million years ago
Locality
Arroyo Seco, south of Cerro Guillermo, Mendoza, Argentina

References

  1. González Riga, B. J. (2003). A new titanosaur (Dinosauria, Sauropoda) from the Upper Cretaceous of Mendoza Province, Argentina. Ameghiniana 40(2): 155-172. gonzálezriga2003a
  2. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Sauropods. Princeton University Press.

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

    jones2026b