Solenodonsaurus janenschi (Broili 1924) Early Permian ~13 cm skull length was considered the sister to all other amniotes (= reptiles) by all prior workers, but here Solenodonsaurus nests as a basal archosauromorph, basal to chroniosuchians. Derived from a sister to Diplovertebron and Eldeceeon, Solenodonsaurus phylogenetically preceded Chroniosuchus and Chroniosaurus.

Overall larger and distinct from Eldeceeon, the skull of Solenodonsaurus was longer and wider. The lacrimal was displaced to the skull roof in situ. The squamosal was larger. The scapulocoracoid was shallow and the ribs were shorter suggesting a lower, wider torso. the interclavicle was kite-shaped with a long posterior process. The humerus was longer and more gracile, twice as long as the radius and ulna.

Broili F von 1924. Ein Cotylosaurier aus der oberkarbonischen Gaskohle von Nürschan in Böhmen. Sitzungsberichte der Mathematisch-Naturwissenschaftlichen Abteilung der Bayerischen Akademie der Wissenschaften zu München 1924: 3-11.

Brough MC and Brough J 1967. Studies on early tetrapods. III. The genus Gephyrostegus. Philosophical Transactions of the Royal Society B252: 147-165.

Carroll RL 1970. The ancestry of reptiles. Philosophical Transactions of the Royal Society B257: 267-308.

Danto M, Witzmann F and Müller J 2012. Redescription and phylogenetic relationships
of Solenodonsaurus janenschi Broili, 1924, from the Late Carboniferous of Nyrany, Czech Republic

Laurin M and Reisz 1999. A new study of Solenodonsaurus janenschi, and a reconsideration of amniote origins and stegocephalian evolution. Canadian Journal of Earth Sciences 36:1239-1255.

Pearson HS 1924. Solenodonsaurus (Broili), a seymouriamorph reptile. Annals and Magazine of Natural History 14:338-343.

wiki/Solenodonsaurus