Titanosaur dinosaurs from the Upper Cretaceous of La Rioja province, NW Argentina

Two Late Cretaceous sauropods reveal titanosaurian dispersal across South America

“…2g ). It forms a conspicuous ridge, which is not evident in related taxa, although it resembles the dorsal tuberosity described for Baurutitan 47 , and also CRILAR-Pv 518c from Los Llanos, east La Rioja 23 . The neural arch of each caudal vertebra is situated over the anterior two-thirds of the centrum, and each is relatively tall with well-developed prezygapophyses and neural spines.…”

“…5 ). Fragmentary findings in NW Argentina 20 , 23 , 73 and Chile 74 suggested the occurrence of non-saltasaurine titanosaurians between Patagonia and Bauru, but the hitherto known evidence was insufficient to conjecture about their phylogenetic affinities. The new phylogenetic analysis recovers Punatitan within a clade of typically “aeolosaurine” taxa, such as Aeolosaurus and Overosaurus , whereas Bravasaurus is nested in a collapsed clade with Brazilian species.…”

“…1a ), along with fragmentary accounts of sauropod dinosaurs in the latter region. However, saltasaurids have not been documented so far in the Bauru Basin nor other units in Brazil 11 , 22 , and the non-saltasaurid specimens in NW Argentina are too fragmentary 23 to allow determination of paleobiogeographic relationships. In addition to saltasaurids, the other high-level clade amongst titanosaurians is the Colossosauria, recently stem-based defined as the most inclusive clade containing Mendozasaurus but not Saltasaurus , nor Epachthosaurus 9 .…”

Life and reproduction of titanosaurians: Isotopic hallmark of mid-palaeolatitude eggshells and its significance for body temperature, diet, and nesting

“…An Early Cretaceous age for the Los Llanos Fm deposits in Sanagasta had first been proposed based on compositional similarities between the egg-bearing sedimentary rocks and hydrothermal veins found in granitoids and pegmatitic intrusions associated to the Gondwanan Cycle and the Sierras Pampeanas orogeny (Galindo et al, 1997;Fiorelli et al, 2012). However, recent microfossil dating in the nearby site of Tama (Carignano et al, 2013;de Sosa Tomas et al, 2017) suggests that a Late Cretaceous age is more likely (Hechenleitner et al, 2018a).…”

Testing the persistence of Carcharodontosauridae (Theropoda) in the Upper Cretaceous of Patagonia based on dental evidence

“…The geographical range can in fact not be restricted to Patagonia but cover even completely to South America, as indicated by the faunistic composition of the Salta, La Rioja and equivalent basins from northwestern Argentina (Novas and Agnolín, 2004;Agnolín and Chiarelli, 2010;D'Emic and Wilson, 2011;Fiorelli et al, 2016;Hechenleitner et al, 2018Hechenleitner et al, , 2020, the Norte Basin of western Uruguay (Perea et al, 2011) or Bauru Basin faunas of Brazil (Martinelli and Teixeira, 2015;Brusatte et al, 2017;Grillo and Delcourt, 2017;Geroto and Bertini, 2019;Langer et al, 2019).…”