The trunk of "Dinocephalosaurus" has at least 26 vertebrae. In "Dinocephalosaurus", there appear to be no lumbar vertebrae, or vertebrae of the trunk lacking ribs. The ribs of the sacrum and tail also do not appear to be fused to their corresponding vertebrae. Each of the gastralia in "Dinocephalosaurus" is composed of three elements instead of four as in "Tanystropheus"; they differ in that "Dinocephalosaurus" only has one element on the midline, while "Tanystropheus" has two elements that combine to form a midline bar.