Alvarezsaurus
Named for Argentine historian Don Gregorio Alvarez, combined with Greek 'sauros' meaning 'lizard', meaning 'Don Gregorio Alvarez's lizard'.
Alvarezsaurus is a genus of alvarezsaurid dinosaur from the Late Cretaceous, living in Argentina approximately 86–83 million years ago. It was a small dinosaur, measuring 1-1.4 m (3.3-4.6 ft) long and weighing approximately 3 kg (6.6 lb). It was found in the Bajo de la Carpa Formation and was named by paleontologist José Bonaparte in 1991 after the historian Don Gregorio Alvarez. The type species is A. calvoi.
Species
Alvarezsaurus calvoi Bonaparte, 1991
Type species
Named for Jorge Calvo, a former student of Jose Bonaparte who discovered the remains near Neuquen City and gifted the material to Bonaparte for study.
- Holotype
- MUCPv 54 , Universidad Nacional del Comahue
- Horizon
- Bajo de la Carpa Formation, Santonian, Late Cretaceous , 85.7–83.6 million years ago
- Locality
- Boca del Sapo, Neuquén, Argentina
References
- Bonaparte, J. F. (1991). Los vertebrados fósiles de la Formación Río Colorado, de la Ciudad de Neuquén y Cercanías, Cretácico Superior, Argentina [The vertebrate fossils of the Rio Colorado Formation, from the city of Neuquén and surrounding areas, Upper Cretaceous, Argentina]. Revista del Museo Argentino de Ciencias Naturales "Bernardino Rivadavia" e Instituto Nacional de Investigación de las Ciencias Naturales: Paleontología 4(3): 17-123. bonaparte1991a
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Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Theropods. Princeton University Press.
Source of the hip height estimate, and the appearance features.
jones2026c