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Dzharatitanis kingi gen. et sp. nov. is based on an isolated anterior caudal vertebra (USNM 538127) from the Upper Cretaceous (Turonian) Bissekty Formation at Dzharakuduk, Uzbekistan. Phylogenetic analysis places the new taxon within the diplodocoid clade Rebbachisauridae. This is the first rebbachisaurid reported from Asia and one of the youngest rebbachisaurids in the known fossil record. The caudal is characterized by a slightly opisthocoelous centrum, ‘wing-like’ transverse processes with large but shallow PRCDF and POCDF, and the absence of a hyposphenal ridge and of TPRL and TPOL. The neural spine has high SPRL, SPDL, SPOL, and POSL and is pneumatized. The apex of neural spine is transversely expanded and bears triangular lateral processes. The new taxon shares with Demandasaurus and the Wessex rebbachisaurid a high SPDL on the lateral side of the neural spine, separated from SPRL and SPOL. This possibly suggests derivation of Dzharatitanis from European rebbachisaurids. This is the second sauropod group identified in the assemblage of non-avian dinosaurs from the Bissekty Formation, in addition to a previously identified indeterminate titanosaurian.

The Rebbachisauridae (Diplodocoidea) comprises small to medium-sized sauropods that diversified at the end of the Early Cretaceous–beginning of the Late Cretaceous in Africa, South America and Europe. The goal of this paper is to review the distribution of fossils assigned to Rebbachisauridae at Early-Late Cretaceous and describe the first occurrence of this group in the Acu Formation, Potiguar Basin, Brazil. The material consists of five isolated caudal vertebrae. The specimens have the combination of some characteristics shared with rebbachisaurid taxa, such as Limaysaurus, Amazonsaurus and Demandasaurus: (i) the anterior and posterior articular facets of the centrum are sub-hexagonal to sub-quadrangular; (ii) they bear a wide base; (iii) the centrum presents an amphicoelic condition; (iv) the centrum lacks pneumatization in both lateral and ventral surfaces; (v) an anterior position of the neural arch is implied by the anteriorly located centroneural suture of the centrum (Salgado et al., 1997; Wilson and Sereno, 1998; Canudo et al., 2018). The rebbachisaurids have been largely used for biogeographical interpretations due to its presence in both Gondwanan and Laurasian continents; the material presented here is a further evidence of this relationship once the specimens show similarities with both European and Argentinean forms. Furthermore, this occurrence enlarges the presence of the group in Brazil and South America, and is important for a better understanding of the faunistic context of the Northeast of South America and its relationship with other Early-Late Cretaceous faunas.

A new medium-sized rebbachisaurid sauropod from the Castrillo la Reina Formation (Upper Barremian-Lower Aptian) in Burgos Province, Demandasaurus darwini gen. et sp. nov., is described. It is known from an incomplete but associated skeleton that includes cranial and post-cranial remains. Demandasaurus darwini gen. et sp. nov. presents 9 autapomorphies in the teeth and vertebrae. Demandasaurus is the first diplodocoid sauropod described from the Cretaceous of the Iberian Peninsula. Its inclusion in the Rebbachisauridae is well supported by our phylogenetic hypothesis, which situates it as a sister group of Nigersaurus from the Aptian of Niger, with which it shares various synapomorphies. The discovery of Demandasaurus provides further evidence of the sporadic use of the Apulian Route by dinosaurs during the Early Cretaceous for moving between the south of Europe (Laurasia) and the north of Africa (Gondwana).

The sauropod of El Oterillo II is a specimen that was excavated from the Castrillo de la Reina Formation (Burgos, Spain), late Barremian–early Aptian, in the 2000s but initially remained undescribed. A tooth and elements of the axial skeleton, and the scapular and pelvic girdle, represent it. It is one of the most complete titanosauriform sauropods from the Early Cretaceous of Europe and presents an opportunity to deepen our understanding of the radiation of this clade in the Early Cretaceous and study the paleobiogeographical relationships of Iberia with Gondwana and with other parts of Laurasia. The late Barremian–early Aptian is the time interval in the Cretaceous with the greatest diversity of sauropod taxa described in Iberia: two titanosauriforms,TastavinsaurusandEuropatitan; and a rebbachisaurid,Demandasaurus. The new sauropodEuropatitan eastwoodin. gen. n. sp. presents a series of autapomorphic characters in the presacral vertebrae and scapula that distinguish it from the other sauropods of the Early Cretaceous of Iberia. Our phylogenetic study locatesEuropatitanas the basalmost member of the Somphospondyli, clearly differentiated from other clades such as Brachiosauridae and Titanosauria, and distantly related to the contemporaneousTastavinsaurus.Europatitancould be a representative of a Eurogondwanan fauna likeDemandasaurus, the other sauropod described from the Castrillo de la Reina Formation. The presence of a sauropod fauna with marked Gondwananan affinities in the Aptian of Iberia reinforces the idea of faunal exchanges between this continental masses during the Early Cretaceous. Further specimens and more detailed analysis are needed to elucidate if this Aptian fauna is caused by the presence of previously unnoticed Aptian land bridges, or it represents a relict fauna from an earlier dispersal event.