Sonorasaurus is a genus of brachiosaurid sauropod dinosaur from the Early to Late Cretaceous (Albian to Cenomanian stages, around 112 to 93 million years ago). Its fossils have been found in southern Arizona, United States. Its name, which means "Sonora lizard", comes from the Sonora River that flows in the Sonoran Desert where its fossils were first found. The type species is S. thompsoni, described by Ratkevich in 1998.
Sonorasaurus is a genus of brachiosaurid sauropod dinosaur from the Early to Late Cretaceous (Albian to Cenomanian stages, around 112 to 93 million years ago). Its fossils have been found in southern Arizona, United States. Its name, which means "Sonora lizard", comes from the Sonora River that flows in the Sonoran Desert where its fossils were first found. The type species is S. thompsoni, described by Ratkevich in 1998.
==Discovery== Fossilized remains were discovered in November 1994 by geology student Richard Thompson in the Turney Ranch Formation in the Whetstone Mountains, located in the Chihuahua Desert region of the Sonoran Desert in southern Arizona. Thompson had investigated a previously almost unexplored region, where fossils proved to be plentiful and directly accessible on the surface. A relatively complete sauropod skeleton was weathering out on a rock wall. He informed paleontologist Ronald Paul Ratkevich of the Arizona-Sonora Desert Museum, Tucson of the find. Ratkevich assembled a team of volunteers and began securing the bones in the spring of 1995; excavations would only end in 1999. He assumed the fossils represented a sauropod but was no expert on that taxon. The curator of geology of the museum, David W. Thayer, thought it might be a therizinosaur, mistaking a tail chevron bone for the long hand claw typical of that group. In 1995, Ratkevich and Tayer first reported the find, already using the name "Sonorasaurus" but informally, so that it remained a nomen nudum.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).