Original paper

A new pachypleurosaur from the Middle Triassic Besano Formation of Northern Italy

Renesto, Silvio; Binelli, Giorgio; Hagdorn, Hans


A new pachypleurosaur, Odoiporosaurus teruzzii gen. et sp. n., is described. The specimen has been collected in the Middle Triassic Besano Formation/Grenzbitumenzone (Northern Italy and Switzerland). It is middle Anisian in age, thus older than the only other pachypleurosaurid from the Besano Formation previously known, Serpianosaurus mirigiolensis, which is of latest Anisian. Odoiporosaurus teruzzii gen. et sp. n. is the sister group of the Serpianosaurus/Neusticosaurus clade and also shares some primitive characters with the older Dactylosaurus/Anarosaurus clade from the Germanic Basin. The discovery of Odoiporosaurus supports the hypothesis that pachypleurosaurs of the Dactylosaurus/Anarosaurus clade immigrated from the eastern Palaeotethys into the Germanic Basin, diversified there during Anisian times, and invaded the earliest intraplatfom basins of the South Alpine realm. Subsequently, during latest Anisian/early Ladinian, the intraplatform basins of the Lombardian Alps acted as a speciation center giving rise to the Serpianosaurus/Neusticosaurus clade.


eosauropterygiagrenzbitumenzonemiddle triassicpachypleurosauriapalaeobiogeographyreptilia