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Striatochelys baba gen. et sp. nov. is a new pan-trionychid from the middle–upper Eocene (late Bartonian–Priabonian, 39–35 Ma) of the Na Duong Basin in northern Vietnam. It represents one of the best documented and most completely known Palaeogene pan-trionychid species from Asia. Striatochelys baba can be diagnosed by: (1) its relatively small size; (2) the absence of a preneural; (3) the presence of well-developed straight ridges on the costals and neurals in adults; (4) ridges more strongly developed posteriorly than anteriorly; and (5) entoplastron callosity in the shape of a bulge. A phylogenetic analysis recovers S. baba within Pan-Trionychinae in an unresolved polytomy with species of the genus Nilssonia. In addition, comparisons of the new taxon with plastomenids, pan-trionychids from the Palaeogene and extant trionychids from Asia demonstrate a particularly close resemblance to Nilssonia spp. Based on the close resemblance between S. baba and 'Trionyx' impressus (a pan-trionychid from the Maoming Basin of southern China), we here assign the latter species to the new genus Striatochelys. The close relationship between S. baba gen. et sp. nov. from the Na Duong Basin and S. impressa comb. nov. from the Maoming Basin further supports the hypothesis that a close connection between both localities existed, as already exemplified by other faunal elements such as pan-geoemydids and crocodylians. [ABSTRACT FROM AUTHOR]

The Lower Cretaceous Lianmuxin Formation (upper Tugulu Group) of the southern Junggar Basin has yielded a vertebrate assemblage of relatively low diversity that is dominated by sinemydid turtles. The assemblage currently includes a single pterosaur taxon, the dsungaripterid Lonchognathosaurus, known from a partial cranium and a partial left wing. Here two additional pterosaur specimens are reported, a well-preserved right distal carpal and a nearly complete but slightly crushed right femur. The carpal almost certainly belongs to a dsungaripterid pterosaur, which is distinct from Lonchognathosaurus. The femur shows many similarities to dsungaripterid femora and is probably also assignable to a dsungaripterid, although it possesses unusually thin bone-walls for the group. Due to a lack of overlapping skeletal material, it cannot be compared to Lonchognathosaurus. These specimens shed new light on the diversity of pterosaurs in the poorly known Lower Cretaceous Lianmuxin Formation of the southern Junggar Basin, indicating that probably more than one dsungaripterid taxon was present in the local assemblage. [ABSTRACT FROM AUTHOR]