New alvarezsaurid (Dinosauria, Theropoda) from Latest Cretaceous of North-western Patagonia with associated eggs.
2012 (English)In: Cretaceous research (Print), ISSN 0195-6671, E-ISSN 1095-998X, Vol. 35, no June, 33-56 p.Article in journal (Refereed) Published
The Alvarezsauridae represents a branch of peculiar basal coelurosaurs with an increasing representationof their Cretaceous radiation distributed worldwide. Here we describe a new member of the group, Bonapartenykus ultimus gen. et sp. nov. from Campanian-Maastrichtian strata of Northern Patagonia, Argentina. Bonapartenykus is represented by a single, incomplete postcranial skeleton. The morphologyof the known skeletal elements suggests close affinities with the previously described taxon from Patagonia, Patagonykus, and both conform to a new clade, here termed Patagonykinae nov. Two incomplete eggs have been discovered in association with the skeletal remains of Bonapartenykus, andseveral clusters of broken eggshells of the same identity were also found in a close proximity. These belong to the new ooparataxon Arriagadoolithus patagoniensis of the new oofamily Arriagadoolithidae, which provides first insights into unique shell microstructure and fungal contamination of eggs laid by alvarezsaurid theropods. The detailed study of the eggs sheds new light on the phylogenetic position of alvarezsaurids within the Theropoda, and the evolution of eggs among Coelurosauria. We suggest thatplesiomorphic alvarezsaurids survived in Patagonia until the latest Cretaceous, whereas these basal forms became extinct elsewhere.
Place, publisher, year, edition, pages
2012. Vol. 35, no June, 33-56 p.
Alvarezsauridae, Patagoninykinae, Bonapartenykus ultimus, Arraigadoolithus patagoniensis, evolution, phylogeny, reproduction, bacterial contamination
Research subject Earth Science with specialization in Historical Geology and Palaeontology
IdentifiersURN: urn:nbn:se:uu:diva-191272DOI: 10.1016/j.cretres.2011.11.014OAI: oai:DiVA.org:uu-191272DiVA: diva2:585228
FunderSwedish Research Council