Juvenile specimen of Megaraptor (Dinosauria, Theropoda) sheds light about tyrannosauroid radiation

Megaraptorids are a group of predatory dinosaurs that inhabited Gondwana from Cenomanian to Santonian times (Late Cretaceous). Phylogenetic relationships of megaraptorids have been matter of recent debate, being alternatively interpreted as basal coelurosaurs, carcharodontosaurian allosauroids, mega...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Porfiri, Juan D, Novas, Fernando Emilio, Calvo, Jorge, Agnolin, Federico L, Ezcurra, Martin Daniel, Cerda, Ignacio Alejandro
Formato: Articulo article acceptedVersion
Lenguaje:English
Publicado: Elsevier 2014
Materias:
Megaraptor
Coelurosauria
Tyrannosauroidea
Patagonia
Ciencias de la Tierra y Medio Ambiente
Acceso en línea:https://rdi.uncoma.edu.ar/handle/uncomaid/18957
Aporte de:
Repositorio Institucional UNCo de Universidad Nacional del Comahue
id I22-R178-uncomaid-18957
record_format dspace
spelling I22-R178-uncomaid-189572025-09-03T16:01:32Z Juvenile specimen of Megaraptor (Dinosauria, Theropoda) sheds light about tyrannosauroid radiation Porfiri, Juan D Novas, Fernando Emilio Calvo, Jorge Agnolin, Federico L Ezcurra, Martin Daniel Cerda, Ignacio Alejandro Megaraptor Coelurosauria Tyrannosauroidea Patagonia Ciencias de la Tierra y Medio Ambiente Megaraptorids are a group of predatory dinosaurs that inhabited Gondwana from Cenomanian to Santonian times (Late Cretaceous). Phylogenetic relationships of megaraptorids have been matter of recent debate, being alternatively interpreted as basal coelurosaurs, carcharodontosaurian allosauroids, megalosauroids, and basal tyrannosauroids. One of the main reasons for such different interpretations is the incomplete nature of most available megaraptorid skeletons and, in particular, the scarce information about their cranial anatomy. Here we describe a partially preserved skeleton of a juvenile specimen of Megaraptor namunhuaiquii that provides substantial new information about the cranial morphology of this Patagonian taxon. The specimen comes from the Upper Cretaceous (Turonian–Coniacian) of the Portezuelo Formation, northwestern Patagonia, Argentina. The anatomy of the new specimen bolsters the recently proposed hypothesis that megaraptorids are nested within Coelurosauria, and possibly within Tyrannosauroidea. The most relevant features that megaraptorans share with tyrannosauroids include several foramina on the premaxillary body, extremely long and straight prenarial process of the premaxilla, incisiviform premaxillary teeth with a D-shaped cross-section, and cranially expanded supratemporal fossae separated from each other by a sharp sagittal median crest on frontals, which was presumably extended caudally above the parietals (not preserved). Information gathered from the present specimen allows to make for the first time a reconstruction of the skull of Megaraptor and hypothesize about evolutionary trends within Tyrannosauroidea. Fil: Porfiri, Juan D. Universidad Nacional del Comahue. Centro Paleontologico Lago Barreales; Argentina. Fil: Novas, Fernando Emilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales; Argentina. Fil: Calvo, Jorge. Universidad Nacional del Comahue. Centro Paleontologico Lago Barreales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fil: Agnolin, Federico L.. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales; Argentina. Fundacion de Historia Natural Felix de Azara; Argentina. Fil: Ezcurra, Martin Daniel. University of Birmingham. School of Geography, Earth and Environmental Sciences; Reino Unido. Fil: Ezcurra, Martin Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fil: Cerda, Ignacio Alejandro. Universidad Nacional de Rio Negro; Argentina. Fil: Cerda, Ignacio Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. 2014 2025-08-27T14:31:27Z 2025-08-27T14:31:27Z Articulo article acceptedVersion https://rdi.uncoma.edu.ar/handle/uncomaid/18957 English https://doi.org/10.1016/j.cretres.2014.04.007 Atribución-NoComercial-CompartirIgual 4.0 https://creativecommons.org/licenses/by-nc-sa/4.0/ application/pdf pp. 35-55 application/pdf Elsevier Cretaceous Research Volume 51
institution Universidad Nacional del Comahue
institution_str I-22
repository_str R-178
collection Repositorio Institucional UNCo
language English
topic Megaraptor
Coelurosauria
Tyrannosauroidea
Patagonia
Ciencias de la Tierra y Medio Ambiente
spellingShingle Megaraptor
Coelurosauria
Tyrannosauroidea
Patagonia
Ciencias de la Tierra y Medio Ambiente
Porfiri, Juan D
Novas, Fernando Emilio
Calvo, Jorge
Agnolin, Federico L
Ezcurra, Martin Daniel
Cerda, Ignacio Alejandro
Juvenile specimen of Megaraptor (Dinosauria, Theropoda) sheds light about tyrannosauroid radiation
topic_facet Megaraptor
Coelurosauria
Tyrannosauroidea
Patagonia
Ciencias de la Tierra y Medio Ambiente
description Megaraptorids are a group of predatory dinosaurs that inhabited Gondwana from Cenomanian to Santonian times (Late Cretaceous). Phylogenetic relationships of megaraptorids have been matter of recent debate, being alternatively interpreted as basal coelurosaurs, carcharodontosaurian allosauroids, megalosauroids, and basal tyrannosauroids. One of the main reasons for such different interpretations is the incomplete nature of most available megaraptorid skeletons and, in particular, the scarce information about their cranial anatomy. Here we describe a partially preserved skeleton of a juvenile specimen of Megaraptor namunhuaiquii that provides substantial new information about the cranial morphology of this Patagonian taxon. The specimen comes from the Upper Cretaceous (Turonian–Coniacian) of the Portezuelo Formation, northwestern Patagonia, Argentina. The anatomy of the new specimen bolsters the recently proposed hypothesis that megaraptorids are nested within Coelurosauria, and possibly within Tyrannosauroidea. The most relevant features that megaraptorans share with tyrannosauroids include several foramina on the premaxillary body, extremely long and straight prenarial process of the premaxilla, incisiviform premaxillary teeth with a D-shaped cross-section, and cranially expanded supratemporal fossae separated from each other by a sharp sagittal median crest on frontals, which was presumably extended caudally above the parietals (not preserved). Information gathered from the present specimen allows to make for the first time a reconstruction of the skull of Megaraptor and hypothesize about evolutionary trends within Tyrannosauroidea.
format Articulo
article
acceptedVersion
author Porfiri, Juan D
Novas, Fernando Emilio
Calvo, Jorge
Agnolin, Federico L
Ezcurra, Martin Daniel
Cerda, Ignacio Alejandro
author_facet Porfiri, Juan D
Novas, Fernando Emilio
Calvo, Jorge
Agnolin, Federico L
Ezcurra, Martin Daniel
Cerda, Ignacio Alejandro
author_sort Porfiri, Juan D
title Juvenile specimen of Megaraptor (Dinosauria, Theropoda) sheds light about tyrannosauroid radiation
title_short Juvenile specimen of Megaraptor (Dinosauria, Theropoda) sheds light about tyrannosauroid radiation
title_full Juvenile specimen of Megaraptor (Dinosauria, Theropoda) sheds light about tyrannosauroid radiation
title_fullStr Juvenile specimen of Megaraptor (Dinosauria, Theropoda) sheds light about tyrannosauroid radiation
title_full_unstemmed Juvenile specimen of Megaraptor (Dinosauria, Theropoda) sheds light about tyrannosauroid radiation
title_sort juvenile specimen of megaraptor (dinosauria, theropoda) sheds light about tyrannosauroid radiation
publisher Elsevier
publishDate 2014
url https://rdi.uncoma.edu.ar/handle/uncomaid/18957
work_keys_str_mv AT porfirijuand juvenilespecimenofmegaraptordinosauriatheropodashedslightabouttyrannosauroidradiation
AT novasfernandoemilio juvenilespecimenofmegaraptordinosauriatheropodashedslightabouttyrannosauroidradiation
AT calvojorge juvenilespecimenofmegaraptordinosauriatheropodashedslightabouttyrannosauroidradiation
AT agnolinfedericol juvenilespecimenofmegaraptordinosauriatheropodashedslightabouttyrannosauroidradiation
AT ezcurramartindaniel juvenilespecimenofmegaraptordinosauriatheropodashedslightabouttyrannosauroidradiation
AT cerdaignacioalejandro juvenilespecimenofmegaraptordinosauriatheropodashedslightabouttyrannosauroidradiation
_version_ 1843667226939359232

Ejemplares similares