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Algora is a recently discovered vertebrate fossil site located in the Cenomanian strata of the Arenas de Utrillas Formation (Guadalajara, Central Spain). This fossil site is rich in turtle remains, but other clades of reptiles are also identified, including plesiosaurs, crocodyliforms and dinosaurs. The only remains of dinosaurs from Algora so far studied corresponded to theropod teeth. However, several sauropod remains are here presented and analyzed, revealing the presence of several shared features with members of Titanosauriformes, some common found in derived members belonging to Lithostrotia clade. This sauropod fossil assemblage corresponds to the richest sauropod fossil accumulation found in the Cenomanian of Europe. In addition, one of the first studies of the pneumatic features in dorsal ribs using CT scan is also provided here. The performed cladistic analysis places the Algora sauropod within Lithostrotia, in a more derived position than Malawisaurus (supported, for example, by the presence of convex posterior articulation up to the posterior section of the tail), in a clade which also includes Rapetosaurus (Maastrichtian, Madagascar) and the Italian indeterminate titanosaur MSNM V7157 (late Aptian–early Albian). The Algora titanosaur and MSNM V7157 are recognized as closely related. This analysis shows the presence of two different lineages (Algora titanosaur + MSNM V7157 and Normanniasaurus, from the Albian of France) in the Early and middle Cretaceous of Europe, and at least one with a Gondwanan origin. The close relationship of the Algora titanosaur and MSNM V7157 suggests a pre-late Aptian faunal contact between the Adriatic Plate and Laurasia, in accordance with several previous studies, which proposed faunal exchanges between Laurasia and Gondwana through the Adriatic plate during the Early Cretaceous.

An additional anterior caudal vertebra of a titanosaurian sauropod Tengrisaurus starkovi from the Lower Cretaceous (Barremian–Aptian) Murtoi Formation of Transbaikalia, Asiatic Russia, reveals new morphological details of this taxon. The new characters include dorsoventrally compressed cotyle and condyle of the centrum and a prominent ridge separating the condyle from the rest of the centrum with the ventral triangular plate (autapomorphy). Parsimony phylogenetic analysis places Tengrisaurus in the predominantly Gondwanan clade Colossosauria + Epachthosaurus on the strict consensus tree and as the sister taxon to the Colossosauria on 66% of the most parsimonious trees. Among Colossosauria, Tengrisaurus is similar with Normanniasaurus from the Albian of France by having a dorsoventrally compressed condyle circumscribed by a distinct ridge, a distinct depression anteroventral to the postzygapophysis, and a deep depression within the postspinal fossa. This discovery suggests that ancestors of the clade Colossosauria were widely distributed in Eurasia during the Early Cretaceous and the clade becomes restricted to the southern continents in the Late Cretaceous.

International audience; New remains of the titanosaurian sauropod Atsinganosaurus velauciensis from its Upper Cretaceous type horizon and type locality in Velaux-La Bastide Neuve (Bouches-du-Rhône Department, Provence) in southern France are described. This locality is considered to be upper Campanian (Argiles et Grès à Reptiles Formation, Aix-en-Provence Basin). The new material consists of skull fragments, including a partial braincase, isolated teeth, elements of the axial skeleton (cervical, dorsal and caudal vertebrae, ribs), and appendicular bones (scapula, humeri, ulna, metacarpals, ilia, ischia, femur, tibia, metatarsal) from at least 3 individuals. Histological investigation shows that the analysed individuals were mature. The emended diagnosis of Atsinganosaurus velauciensis includes a pubic peduncle of the ilium with a posterior concave surface in its distal half, surrounded by two sharp ridges. Equations for predicting body mass and size in sauropods suggest a body size up to 12 m and a body mass of at least 3.5–5 tonnes for the largest individuals.A phylogenetic analysis including 29 sauropod taxa was performed, with the European titanosaurs Atsinganosaurus, Ampelosaurus, Lirainosaurus, Lohuecotitan, Paludititan (Late Cretaceous) and Normanniasaurus (Early Cretaceous) all scored in the same analysis for the first time. Atsinganosaurus and Ampelosaurus form a clade that is phylogenetically proximal to Lirainosaurus within Lithostrotia – a clade here named Lirainosaurinae nov. – whereas Lohuecotitan and Paludititan form a clade towards the base of Lithostrotia. Normanniasaurus is resolved outside Lithostrotia, but within Titanosauria. From a palaeobiogeographical perspective, the phylogenetic results suggest that European titanosaurs belong to at least three distinct lineages and that two lithostrotian lineages were present during the latest Cretaceous in the European archipelago.