| rdfs:comment | - The only specimen includes a neck vertebra, a back vertebra and part of a second, six tail vertebra, two chevrons, fragmentary ribs, the right sternal plate, the right shoulder blade, and the left thigh bone (femur).[1] This individual may have measured 6.5 metres (21 ft) when alive; the thigh bone measures 76 centimetres in length.[1] However, the vertebral neural arches have been found separated from the vertebral centra, indicating that these elements were not fused with each other; thus, this individual probably was not fully grown.[1]
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| abstract | - The only specimen includes a neck vertebra, a back vertebra and part of a second, six tail vertebra, two chevrons, fragmentary ribs, the right sternal plate, the right shoulder blade, and the left thigh bone (femur).[1] This individual may have measured 6.5 metres (21 ft) when alive; the thigh bone measures 76 centimetres in length.[1] However, the vertebral neural arches have been found separated from the vertebral centra, indicating that these elements were not fused with each other; thus, this individual probably was not fully grown.[1] Early sauropodomorphs were primitively bipedal (two-legged). Isanosaurus, being one of the first sauropods known, already shows a quadrupedal locomotion (with all four legs on the ground).[1] The legs were column-like, as indicated by the robust and straight thigh bone.[1] In prosauropods, but also in the very basal sauropod Antetonitrus, the thigh bone was slightly sigmoidal (S-curved).[2] Also, like in other sauropods, bony processes of the femur were reduced in Isanosaurus; most notably, the lesser trochanter was lacking.[1] Additional important features can be found in the vertebrae. The neck vertebrae were distinctly opisthocoelous (convex at the front and hollow at the back), forming ball-and-socket joints with neighbouring vertebrae. The tail vertebrae, on the other hand, were amphicoelous (concave at both ends).[1] The dorsal neural spines were very high, like those of some later sauropods, unlike the low prosauropod neural spines.[1] The lateral sides of the vertebrae were concave, but not deeply excavated (a structure known as pleurocoels) as in later sauropods.
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