Two Late Cretaceous sauropods reveal titanosaurian dispersal across South America

HECHENLEITNER, E. MARTÍN; LEUZINGER, LÉA; MARTINELLI, AGUSTÍN G.; ROCHER, SEBASTIÁN; FIORELLI, LUCAS E.; TABORDA, JEREMÍAS R. A.; SALGADO, LEONARDO

Communications Biology

Nature

Año: 2020 vol. 3

South American titanosaurians have been central to the study of the evolution of Cretaceoussauropod dinosaurs. Despite their remarkable diversity, the fragmentary condition of severaltaxa and the scarcity of records outside Patagonia and southwestern Brazil have hindered thestudy of continental-scale paleobiogeographic relationships. We describe two new LateCretaceous titanosaurians from Quebrada de Santo Domingo (La Rioja, Argentina), whichhelp to fill a gap between these main areas of the continent. Our phylogenetic analysisrecovers both new species, and several Brazilian taxa, within Rinconsauria. The data suggestthat, towards the end of the Cretaceous, this clade spread throughout southern SouthAmerica. At the same locality, we discovered numerous accumulations of titanosaurian eggs,likely related to the new taxa. With eggs distributed in three levels along three kilometres, thenew site is one of the largest ever found and provides further evidence of nesting sitephilopatry among Titanosauria