Classification
The closest relatives of Cetiosaurus appear to be Barapasaurus and the South American Patagosaurus. Together they comprise the Cetiosauridae, which was previously a large ill-defined family of primitive sauropods. It must also be noted that Chebsaurus is often referred to the Cetiosauridae, and that Barapasaurus has been assigned to the Vulcanodontidae, due to its having cervical vertebrae that resemble other cetiosaurids, but a narrow sacrum that is a defining factor for vulcanodontids.
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