1
|
Aranciaga Rolando AM, Novas FE, Calvo JO, Porfiri JD, Dos Santos DD, Lamanna MC. Reconstruction of the pectoral girdle and forelimb musculature of Megaraptora (Dinosauria: Theropoda). Anat Rec (Hoboken) 2023. [PMID: 36647300 DOI: 10.1002/ar.25128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 09/18/2022] [Accepted: 11/06/2022] [Indexed: 01/18/2023]
Abstract
Megaraptora is a group of enigmatic, carnivorous non-avian theropod dinosaurs from the Cretaceous of Asia, Australia, and especially South America. Perhaps the most striking aspect of megaraptoran morphology is the large, robustly constructed forelimb that, in derived members of the clade, terminates in a greatly enlarged manus with hypertrophied, raptorial unguals on the medialmost two digits and a substantially smaller ungual on digit III. The unique forelimb anatomy of megaraptorans was presumably associated with distinctive functional specializations; nevertheless, its paleobiological significance has not been extensively explored. Here we draw from observations of the pectoral girdle and forelimb skeletons of Megaraptora and myological assessments of other archosaurian taxa to provide a comprehensive reconstruction of the musculature of this anatomical region in these singular theropods. Many muscle attachment sites on megaraptoran forelimb bones are remarkably well developed, which in turn suggests that the muscles themselves were functionally significant and important to the paleobiology of these theropods. Furthermore, many of these attachments became increasingly pronounced through megaraptoran evolutionary history, being substantially better developed in derived taxa such as Australovenator wintonensis and especially Megaraptor namunhuaiquii than in early branching forms such as Fukuiraptor kitadaniensis. When considered alongside previous range of motion hypotheses for Australovenator, our results indicate that megaraptorans possessed a morphologically and functionally specialized forelimb that was capable of complex movements. Notable among these were extensive extension and flexion, particularly in the highly derived manus, as well as enhanced humeral protraction, attributes that very probably aided in prey capture.
Collapse
Affiliation(s)
| | - Fernando E Novas
- Museo Argentino de Ciencias Naturales "Bernardino Rivadavia," CONICET, CABA, Argentina
| | - Jorge O Calvo
- Grupo de Transferencia Proyecto Dino, CIGPat, Facultad de Ingeniería, Departamento de Geología y Petróleo, Universidad Nacional del Comahue, Neuquén, Argentina.,Parque Natural Geo-Paleontológico Proyecto Dino, Grupo de Transferencia Proyecto Dino, Facultad de Ingeniería, Universidad Nacional del Comahue, Neuquén, Argentina.,Facultad de Ciencias Exactas y Naturales, Universidad Nacional de la Pampa, Santa Rosa, La Pampa, Argentina
| | - Juan D Porfiri
- Museo de Ciencias Naturales, Universidad Nacional del Comahue, Neuquén, Argentina.,Cátedra de Reptiles Mesozoicos, Facultad de Ingeniería, Universidad Nacional del Comahue, Neuquén, Argentina.,Museo del Desierto Patagónico de Añelo, Municipalidad de Añelo/Universidad Nacional del Comahue, Neuquén, Argentina
| | - Domenica D Dos Santos
- Museo de Ciencias Naturales, Universidad Nacional del Comahue, Neuquén, Argentina.,Cátedra de Reptiles Mesozoicos, Facultad de Ingeniería, Universidad Nacional del Comahue, Neuquén, Argentina.,Museo del Desierto Patagónico de Añelo, Municipalidad de Añelo/Universidad Nacional del Comahue, Neuquén, Argentina
| | - Matthew C Lamanna
- Section of Vertebrate Paleontology, Carnegie Museum of Natural History, Pittsburgh, Pennsylvania, USA
| |
Collapse
|
2
|
Porfiri JD, Calvo JO, Santos DD. A new small deinonychosaur (Dinosauria: Theropoda) from the Late Cretaceous of Patagônia, Argentina. AN ACAD BRAS CIENC 2011; 83:109-16. [DOI: 10.1590/s0001-37652011000100007] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2010] [Accepted: 09/14/2010] [Indexed: 11/22/2022] Open
Abstract
Here we report on a new small deinonychosaurian theropod, Pamparaptor micros gen. et sp. nov., from the Late Cretaceous of Patagônia, Argentina. Pamparaptor micros exhibits a pedal structure previously unknown among South Américan deinonychosaurians. The new material provides new evidence about the morphology and taxonomic diversity of Patagônian deinonychosaurs. Pamparaptor is the smaller non-avialae Patagônian deinonychosaur, probably with about 0.50-0.70 meters, long. The pedal construction resembles, that of Troodontid or basal Dromaeosaurids. Nevertheless, up to now, we considered Pamparaptor a peculiar Patagônian Dromaeosaurid with troodontid-like pes.
Collapse
|
3
|
Novas FE, Pol D, Canale JI, Porfiri JD, Calvo JO. A bizarre Cretaceous theropod dinosaur from Patagonia and the evolution of Gondwanan dromaeosaurids. Proc Biol Sci 2009; 276:1101-7. [PMID: 19129109 DOI: 10.1098/rspb.2008.1554] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Fossils of a predatory dinosaur provide novel information about the evolution of unenlagiines, a poorly known group of dromaeosaurid theropods from Gondwana. The new dinosaur is the largest dromaeosaurid yet discovered in the Southern Hemisphere and depicts bizarre cranial and postcranial features. Its long and low snout bears numerous, small-sized conical teeth, a condition resembling spinosaurid theropods. Its short forearms depart from the characteristically long-armed condition of all dromaeosaurids and their close avian relatives. The new discovery amplifies the range of morphological disparity among unenlagiines, demonstrating that by the end of the Cretaceous this clade included large, short-armed forms alongside crow-sized, long-armed, possibly flying representatives. The new dinosaur is the youngest record of dromaeosaurids from Gondwana and represents a previously unrecognized lineage of large predators in Late Cretaceous dinosaur faunas mainly dominated by abelisaurid theropods.
Collapse
Affiliation(s)
- Fernando E Novas
- CONICET, Museo Argentino de Ciencias Naturales Bernardino Rivadavia, Avenida Angel Gallardo 470, Buenos Aires 1405, Argentina.
| | | | | | | | | |
Collapse
|
4
|
Calvo JO, Porfiri JD, González-Riga BJ, Kellner AWA. A new Cretaceous terrestrial ecosystem from Gondwana with the description of a new sauropod dinosaur. AN ACAD BRAS CIENC 2007; 79:529-41. [PMID: 17768539 DOI: 10.1590/s0001-37652007000300013] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2007] [Accepted: 08/01/2007] [Indexed: 11/21/2022] Open
Abstract
A unique site at the northern area of Patagonia (Neuquén, Argentina) reveals a terrestrial ecosystem preserved in a detail never reported before in a Late Cretaceous deposit. An extraordinary diversity and abundance of fossils was found concentrated in a 0.5 m horizon in the same quarry, including a new titanosaur sauropod, Futalognkosaurus dukei n.gen., n.sp, which is the most complete giant dinosaur known so far. Several plant leaves, showing a predominance of angiosperms over gymnosperms that likely constituted the diet of F. dukei were found too. Other dinosaurs (sauropods, theropods, ornithopods), crocodylomorphs, pterosaurs, and fishes were also discovered, allowing a partial reconstruction of this Gondwanan continental ecosystem.
Collapse
Affiliation(s)
- Jorge O Calvo
- Proyecto Dino, Centro Paleontológico Lago Barreales, Universidad Nacional del Comahue, Neuquén, Argentina.
| | | | | | | |
Collapse
|