Mierasaurus can be excluded from the Titanosauriformes due to the solid internal structure of its vertebrae and ribs, which indicates they lack air-filled cavities.
Uniquely, on the bottom of the internal cavity of the atlantal intercentrum (term used for the unfused lower half of vertebral centrum of the atlas) in Mierasaurus, there is a pair of depressions that articulates with the odontoid process of the axis (second cervical).
Moabosaurus lacks these depressions, and the cervical rib articulation (parapophysis) is more robust.
As seen in Kaatedocus, the laminae extending from the neural spines to the prezygapophysis of the cervical vertebrae are well-developed and cap depressions underneath.
The cervical neural spines are not strongly split (bifurcated) in Mierasaurus, less so than those of Turiasaurus.
Also unlike Moabosaurus, there are no keels or hollows on the bottom of the cervical centra.
None of the cervical ribs are visibly bifurcated either, unlike both Turiasaurus and Moabosaurus, although there are small upward projections at the tips of the first few cervical ribs which may represent incipient or rudimentary bifurcation.
There is a ridge on the side of the tubercle of each rib, which is a unique diagnostic feature of Mierasaurus.

The rear dorsal vertebrae in Mierasaurus are concave on both ends (amphicoelous), whereas the opposite (opisthicoelous) is true for Mierasaurus, Camarasaurus, and titanosauriforms.
Mierasaurus does not have the prespinal laminae (ridges on the front of the spine) present in the rear dorsal vertebrae of Moabosaurus, and the articular process known as the hyposphene is triangular in Mierasaurus while it is rectangular in Moabosaurus.
However, Mierasaurus shares with Moabosaurus dorsal neural spines with spinodiapophyseal laminae that bifurcate towards the top of each spine, with one branch extending forwards and one backwards.
The caudal (tail) vertebrae are concave in front and convex behind (procoelous), as in Turiasaurus, Moabosaurus, Losillasaurus, and the Titanosauria.
Also like titanosauriforms, the neural arches are located on the front halves of each centrum, and the haemal canals are long compared to the haemal arches that form them, at 41% of the bones' length.
There are characteristic depressions at the lower outer sides of the haemal arches.
Mierasaurus can be excluded from the Titanosauriformes due to the solid internal structure of its vertebrae and ribs, which indicates they lack air-filled cavities. Uniquely, on the bottom of the internal cavity of the atlantal intercentrum (term used for the unfused lower half of vertebral centrum of the atlas) in Mierasaurus, there is a pair of depressions that articulates with the odontoid process of the axis (second cervical). Moabosaurus lacks these depressions, and the cervical rib articulation (parapophysis) is more robust. As seen in Kaatedocus, the laminae extending from the neural spines to the prezygapophysis of the cervical vertebrae are well-developed and cap depressions underneath. The cervical neural spines are not strongly split (bifurcated) in Mierasaurus, less so than those of Turiasaurus. Also unlike Moabosaurus, there are no keels or hollows on the bottom of the cervical centra. None of the cervical ribs are visibly bifurcated either, unlike both Turiasaurus and Moabosaurus, although there are small upward projections at the tips of the first few cervical ribs which may represent incipient or rudimentary bifurcation. There is a ridge on the side of the tubercle of each rib, which is a unique diagnostic feature of Mierasaurus.
The rear dorsal vertebrae in Mierasaurus are concave on both ends (amphicoelous), whereas the opposite (opisthicoelous) is true for Mierasaurus, Camarasaurus, and titanosauriforms. Mierasaurus does not have the prespinal laminae (ridges on the front of the spine) present in the rear dorsal vertebrae of Moabosaurus, and the articular process known as the hyposphene is triangular in Mierasaurus while it is rectangular in Moabosaurus. However, Mierasaurus shares with Moabosaurus dorsal neural spines with spinodiapophyseal laminae that bifurcate towards the top of each spine, with one branch extending forwards and one backwards. The caudal (tail) vertebrae are concave in front and convex behind (procoelous), as in Turiasaurus, Moabosaurus, Losillasaurus, and the Titanosauria. Also like titanosauriforms, the neural arches are located on the front halves of each centrum, and the haemal canals are long compared to the haemal arches that form them, at 41% of the bones' length. There are characteristic depressions at the lower outer sides of the haemal arches.
Mierasaurus