Protopyknosia is an extinct clade of archosauriform reptiles from the Late Triassic of India and the United States. First identified by Sterling Nesbitt et al. in 2021,[1] the clade contains two genera: Kranosaura and Triopticus. Members of Protopyknosia characteristically have an unusually domed head reminiscent of the later pachycephalosaurian dinosaurs in an example of convergent evolution.[2]

Protopyknosia
Temporal range: Late Triassic,
~229–211 Ma Carnian-Norian
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Clade: Archosauromorpha
Clade: Archosauriformes
Clade: Protopyknosia
Nesbitt et al., 2021
Genera

References edit

  1. ^ Nesbitt, S. J.; Stocker, M. R.; Chatterjee, S.; Horner, J. R.; Goodwin, M. B. (2021). "A remarkable group of thick-headed Triassic Period archosauromorphs with a wide, possibly Pangean distribution". Journal of Anatomy. 239 (1): 184–206. doi:10.1111/joa.13414. PMC 8197959. PMID 33660262.
  2. ^ Stocker, M.R.; Nesbitt, S.J.; Criswell, K.E.; Parker, W.G.; Witmer, L.M.; Rowe, T.B.; Ridgely, R.; Brown, M.A. (2016). "A Dome-Headed Stem Archosaur Exemplifies Convergence among Dinosaurs and Their Distant Relatives". Current Biology. 26 (19): 2674–2680. doi:10.1016/j.cub.2016.07.066. PMID 27666971.