Mamenchisaurus
extinct genus of sauropod dinosaurs (Sauropoda)
Mamenchisaurus ( mə-MUN-chee-SOR-əs, or spelling pronunciation ) is an extinct genus of sauropod dinosaurs known for their remarkably long necks, which made up nearly half the total body length. Numerous species have been assigned to the genus; however, the validity of these assignments has been questioned. Fossils have been found in the Sichuan Basin and Yunnan Province in China. Several species from the Upper Shaximiao Formation, whose geologic age is uncertain, have been described. However, evidence suggests this formation to be no earlier than the Oxfordian stage of the Late Jurassic. M. sinocanadorum dates to the Oxfordian stage (161.2 to 158.7 mya), and M. anyuensis to the Aptian stage of the Early Cretaceous (around 114.4 mya). Most species were medium-large to large sauropods, measuring roughly 15 to 26 meters (49 to 85 ft) in length—possibly up to 35 meters (115 ft), based on two undescribed vertebrae.
History and species
Mamenchisaurus was first discovered in 1952 on the construction site of the Yitang Highway in Sichuan Province, China. The fossil site belonged to the Upper Shaximiao Formation, dating to at least the Late Jurassic. The partial skeleton fossil was later studied and named Mamenchisaurus constructus in 1954 by the renowned Chinese paleontologist Professor C. C. Young.
Begin with the source’s own compact description: “Mamenchisaurus” is extinct genus of sauropod dinosaurs (Sauropoda). The dossier treats that line as a proposition to test through Mamenchisaurus, extinct and genus, not as a finished interpretation.
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Datasets, specimens, observations and peer-reviewed methods provide the appropriate test for the technical claims summarized here. The source revision retrieved here is dated Sep 22, 2026. The linked authority identifier is Q131038. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1952 and 1954.
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This entry incorporates text from “Mamenchisaurus” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.