Nesbitt (2011) and his Characters – part 3 – Vancleavea + Archosauria

Following remarks from fellow paleontologists asking for my study to include more Nesbitt (2011) characters in the large reptile study, I thought we should dive right into them, taking a few days to digest them all — a bite at a time. Earlier we considered more basal clades in part 1 and part 2.

Nesbitt Characters for Vancleavea + Archosauria
Sterling Nesbitt (SN) reported, (1) Postparietal(s) absent (146-1). Postparietals are absent in pterosaurs (Bennett, 1996).
Note: As in certain lepidosaurs, including all fenestrasaurs.

(2) Postaxial intercentra absent (177-1). Postaxial intercentra are absent in pterosaurs (Bennett, 1996).
Note: As in certain lepidosaurs, including all fenestrasaurs.

(3) Ectepicondylar flange of the humerus absent (234-1). An ectepicondylar flange is absent in pterosaurs (Bennett, 1996).
Note: As in certain lepidosaurs, including all fenestrasaurs.

(4) Distal condyles of the femur not projecting markedly beyond shaft (318-1). Distal condyles of the femur not projecting markedly beyond shaft in basal pterosaurs.
Note: As in certain lepidosaurs, including all fenestrasaurs.

Long time readers will remember that Vancleavea nests as a thalattosaur close to Helveticosaurus, not an archosauriform, as recovered by the large reptile tree.

Tomorrow: Crurotarsi (Phytosauria + Crocodylomorpha)

As always, I encourage readers to see specimens, make observations and come to your own conclusions. Test. Test. And test again.

Evidence and support in the form of nexus, pdf and jpeg files will be sent to all who request additional data.

References
Nesbitt SJ 2011.
 The early evolution of archosaurs: relationships and the origin of major clades. Bulletin of the American Museum of Natural History 352: 292 pp.

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