Artículos de revistas
A New Upper Cretaceous Titanosaur Nesting Site From La Rioja (nw Argentina), With Implications For Titanosaur Nesting Strategies
Registro en:
Palaeoecology. Wiley-blackwell, v. 59, p. 433 - 446, 2016.
0031-0239
1475-4983
WOS:000374647700008
10.1111/pala.12234
Autor
Hechenleitner
E. Martin; Fiorelli
Lucas E.; Grellet-Tinner
Gerald; Leuzinger
Lea; Basilici
Giorgio; Taborda
Jeremias R. A.; De la Vega
Sergio R.; Bustamante
Carlos A.
Institución
Resumen
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Cretaceous titanosaur nesting sites are currently known only from Europe, Asia and South America. In the latter, only the Auca Mahuevo and Sanagasta nesting sites have been confidently assigned to this clade of sauropod dinosaurs. Here we report the discovery of the first eggs and egg clutches found at Tama, a new Upper Cretaceous fossiliferous locality in the Los Llanos Formation, Sierra de Los Llanos (La Rioja, NW Argentina). At least five egg clutches, several partially preserved, isolated eggs and many eggshell fragments were discovered in a single outcrop of a sandstone horizon which represents a cumulative palaeosol profile. Although the mechanical and digital preparation of eggs did not reveal any embryonic remains in ovo, the morphology of the eggs and eggshells closely matches that of titanosaur eggs and eggshells found worldwide. The morphology and spatial grouping of the titanosaur eggs from Tama, along with geological observations support a burrow-nesting strategy for these dinosaurs. Although the Sanagasta and Tama eggs were found in the same stratigraphical unit and share several morphological characters, they clearly differ in shell thickness and egg size. This, coupled with the interpretation of different sedimentary contexts for these nesting sites, strongly suggests that at least two different titanosaur species nested in La Rioja during the Late Cretaceous, using different nesting strategies. The occurrence of this new titanosaur nesting site in a semiarid palaeoenvironment represents an interesting case study for the reproductive biology of the titanosaur dinosaurs, particularly their labile nesting behaviour. 59 3 433 446 CONICET Jurassic Foundation Agencia Nacional de Promocion Cientifica y Tecnologica [PICT 2012-0421] FAPESP [2012/23209-0] Municipio A. V. Penaloza, La Rioja Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)