INVESTIGADORES
GOMEZ Raul Orencio
artículos
Título:
The youngest South American rhynchocephalian, a survivor of the K/Pg extinction
Autor/es:
APESTEGUÍA, S.; GÓMEZ, R.O.; ROUGIER, G.W.
Revista:
PROCEEDINGS OF THE ROYAL SOCIETY OF LONDON. SERIES B: BIOLOGICAL SCIENCES.
Editorial:
ROYAL SOC
Referencias:
Lugar: Londres; Año: 2014 vol. 281 p. 1 - 6
ISSN:
0962-8452
Resumen:
Rhynchocephalian lepidosaurs, though once widespread worldwide, are represented today only by the tuatara (Sphenodon) of New Zealand. After their apparent early Cretaceous extinction in Laurasia, they survived in southern continents. In South America, they are represented by different lineages of Late Cretaceous eupropalinal forms until their disappearance by theCretaceous/Palaeogene (K/Pg) boundary.We describe here the only unambiguous Palaeogene rhynchocephalian from South America; this new taxon is a younger species of the otherwise Late Cretaceous genus Kawasphenodon. Phylogenetic analysis confirms the allocation of the genus to the clade Opisthodontia. The new form from the Palaeogene of Central Patagonia is much smaller than Kawasphenodon expectatus from the Late Cretaceous of Northern Patagonia. The new species shows that at least one group of rhynchocephalians not related to the extant Sphenodon survived in SouthAmerica beyond the K/Pg extinction event. Furthermore, it adds to other trans-K/Pg ectothermtetrapod taxa, suggesting that the end-Cretaceous extinction affected Patagonia more benignly than the Laurasian landmasses.