Open Paleo

Petrobrasaurus

Filippi et al., 2011 pet-RO-brah-SOR-us

Named after Petrobras, the Brazilian state oil company that operated in the region where the fossil was found, combined with Greek sauros meaning 'lizard'; meaning 'Petrobras lizard'

89.8–83.6 million years ago Coniacian–Santonian, Late Cretaceous
Late Cretaceous stages

Petrobrasaurus is a genus of herbivorous sauropod dinosaur. It is a titanosaur which lived during the upper Cretaceous period (Coniacian-Santonian age) in what is now Rincón de los Sauces, Patagonia, Argentina. It is known from the holotype MAU-Pv-PH-449 — a partial disarticulated skeleton recovered from the Plottier Formation (Neuquén Basin), Argentina. This genus was named by Leonardo S. Filippi, José Ignacio Canudo, Leonardo J. Salgado, Alberto C. Garrido, Rodolfo A. Garcia, Ignacio A. Cerda and Alejandro Otero in 2011, and the type species is Petrobrasaurus puestohernandezi. The generic name is derived from "Petrobras" (oil company) and saurus, "lizard". The specific name refers to the Puesto Hernández oil field, where the fossil remains were found.

Diagnosis

  1. Accessory posterior centrodiapophyseal lamina more developed than posterior centrodiapophyseal lamina in dorsal vertebrae
  2. Posterior centroparapophyseal lamina extends from contact with accessory posterior centrodiapophyseal lamina
  3. Broad concave surface delimited by posterior centroparapophyseal lamina rim and dorsal pleurocoel edge
  4. Deep sub-circular fossa bounded by accessory posterior and posterior centrodiapophyseal laminae
  5. T-shaped anteroposterior expansion of neural arch laminae in dorsal and anterior caudal vertebrae
  6. Deep fossa between spinoprezygapophysial lamina and postzygapophysis in anterior caudal vertebrae, bearing small fossae
  7. Prespinal lamina distally thickened in anterior caudal vertebrae
  8. Sub-circular small fossae on both sides of prespinal lamina base in anterior caudal vertebrae

Species

Petrobrasaurus puestohernandezi Filippi et al., 2011

Type species

Named for the Puesto Hernández oil field in Neuquén, Argentina, where the holotype fossil remains were found.

Holotype
MAU-Pv-PH-449/1, MAU-Pv-PH-449/2, MAU-Pv-PH-449/3, MAU-Pv-PH-449/4, MAU-Pv-PH-449/5, MAU-Pv-PH-449/6, MAU-Pv-PH-449/7, MAU-Pv-PH-449/8, MAU-Pv-PH-449/9, MAU-Pv-PH-449/10, MAU-Pv-PH-449/11, MAU-Pv-PH-449/12, MAU-Pv-PH-449/13, MAU-Pv-PH-449/14, MAU-Pv-PH-449/15, MAU-Pv-PH-449/16, MAU-Pv-PH-449/17, MAU-Pv-PH-449/18, MAU-Pv-PH-449/19, MAU-Pv-PH-449/20, MAU-Pv-PH-449/22, MAU-Pv-PH-449/25, MAU-Pv-PH-449/26, MAU-Pv-PH-449/27, MAU-Pv-PH-449/29, MAU-Pv-PH-449/30, MAU-Pv-PH-449/31, MAU-Pv-PH-449/32, MAU-Pv-PH-449/35, MAU-Pv-PH-449/36, MAU-Pv-PH-449/37 , Museo Argentino Urquiza, Rincón de los Sauces
Material
Two incomplete teeth, posterior middle cervical vertebra, three incomplete posterior dorsal vertebrae, incomplete posterior dorsal arch, incomplete dorsal vertebral centrum, incomplete first caudal centrum, five anterior caudal vertebrae, right humerus, right and left sternal plates, four metacarpals, right and left femur, left tibia lacking distal end, distal end of right tibia, distal iliac peduncle fragment, left pubis, haemal arch fragments, dorsal rib fragments, cervical rib fragments.
Horizon
Plottier Formation, Coniacian–Santonian, Late Cretaceous , 89.8–83.6 million years ago
Locality
PH 1597, Neuquén, Argentina

References

  1. Filippi, L. S.; Canudo, J. I.; Salgado, J. L.; Garrido, A.; García, R.; Cerda, I. A.; Otero, A. (2011). A new sauropod titanosaur from the Plottier Formation (Upper Cretaceous) of Patagonia (Argentina). Geologica Acta 9(1): 1-12. Edicions de la Universitat de Barcelona. doi:10.1344/105.000001648 filippi2011a
  2. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Sauropods. Princeton University Press.

    Source of the body length, mass, and hip height estimates.

    jones2026b