Genus: Sonorasaurus RATKEVICH, 1998
Etymology: From the Hispanicized Opata Indian term, Sonora, referring to the Sonora River, Pima County, Arizona, used here as being part of the greater Sonoran Desert region as a general province, and Greek, sauros, “lizard”: Sonoran Lizard.

Species: thompsoni RATKEVICH, 1998
Etymology: In honor of Richard Thompson, who discovered the specimen.

Holotype: ASDM 500

Locality: “Sonorasaurus” Quarry, southwestern foothills of Whetstone Mountains, Pima County, Arizona.

Horizon: Turney Ranch Formation, Bisbee Group.


Age: Albian Stage, Middle Gallic Subepoch, Upper Early Cretaceous Epoch, Early Cretaceous.

Material: Left ulna, radii, left (?) complete McI, complete McII, proximal and distal ends of McIII (?), proximal and distal ends of McIV (?), distal ½ and marginal elements of left ilium, distal 1/3 of ischium, acetabulum, medial portions of pubis and possible ischium, distal half of left femur, mid schaft of right ulna, left tibia (?), left fibula, partial right fibula (?), MtI, MtII, MtIV, MtV, phalanx I-1, phalanx II-1, phalanx IV-1, phalanx II-3, ungual digit 1, ungual digit 2, first (?) second (?), and third dorsal vertebrae, caudal vertebrae 5-12 (est), chevron fragments, dorsal and cervical ribs, and 2 gastroliths.
Note: What was thought to be a skull is actually a fragmentary vertebra.

Breakdown of some of the material:


ASDM-500-4: Dorsal vertebra.

ASDM-500-296: Caudal vertebra.

ASDM-500-7: Caudal vertebra.

ADSM-500-9: Caudal centra.