December 25 , 2016:
We here present a description of the two rib fragments referred to Euscolosuchus olseni and review their possible implications....
The function of expanded ribs has been extensively discussed, but few conclusions have been reached. In the case of Euscolosuchus olseni, one plausible explanation is increased rigidity of the trunk region. This would be consistent with the interlocking mode of articulation between the cervical and dorsal osteoderms, which would have largely suppressed lateral flexion in the neck and trunk regions. It is also possible that the osteoderms and ribs restricted movement of the trunk to reduce torsional or shear stresses on the vertebral column. Based on the structure of the single dorsal vertebra, which has a low neural spine, and the overlying osteoderms with long anterolateral processes, there was little room for epaxial musculature. Unfortunately, too little is still known about the structure of the skeleton of this unusual pseudosuchian to explore the possible functional significance of the postcranial axial skeleton in more detail.
Torsten M. Scheyer & Hans-Dieter Sues (2016)
Expanded dorsal ribs in the Late Triassic pseudosuchian reptile Euscolosuchus olseni.
Journal of Vertebrate Paleontology: e1248768
doi: http://dx.doi.org/10.1080/02724634.2017.1248768
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