A new titanosauriform with European affinities in the Early Cretaceous of Brazil: insights on Somphospondyli phylogeny, histology and biogeography

A non-titanosaur Somphospondyli specimen unearthed from Early Cretaceous (Aptian) deposits of north-eastern Brazil allowed the establishment of a new taxon, Dasosaurus tocantinensis gen. et sp. nov. Shared synapomorphic traits, notably a complex of three anteroposteriorly elongated ridges in the middle and posterior caudal vertebrae, with a groove above the ventral one, and a well-developed lateral bulge on the femur, support the position of the new sauropod as sister to Garumbatitan morellensis, from the Barremian of Spain. Osteohistological patterns recognized in D. tocantinensis include a mixture of traits previously recognized separately in early diverging neosauropods and later titanosaurs, including an external fundamental system and remains of primary laminar tissue, along with a high degree of secondary remodelling. Apart from expanding the known diversity of Early Cretaceous sauropods in the northern part of South America, this discovery highlights biogeographical connections with more northern Gondwanan areas, as well as Europe. In fact, numerical biogeographical analyses suggest that the clade formed by D. tocantinensis and Ga. morellensis had a European origin, with the lineage including D. tocantinensis dispersing to South America via northern Africa at some point between the Valanginian and Aptian.https://zoobank.org/urn:lsid:zoobank.org:pub:0BF20DD1-159D-40EE-8E46-3EE88771470A