Megaraptor
| Megaraptor | |
|---|---|
| |
| Reconstructed hand | |
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Clade: | Dinosauria |
| Clade: | Saurischia |
| Clade: | Theropoda |
| Clade: | †Megaraptora |
| Family: | †Megaraptoridae |
| Genus: | †Megaraptor Novas 1998 |
| Species: | †M. namunhuaiquii
|
| Binomial name | |
| †Megaraptor namunhuaiquii Novas 1998
| |
Megaraptor (lit. 'large thief') is a
Description
Megaraptor was initially described as a giant dromaeosaur, known primarily from a single claw (about 30 cm long) that resembled the sickle-shaped foot claw of dromaeosaurids.[2] The discovery of a complete front limb, however, showed that this giant claw actually came from the first finger of the hand. In 2010, Gregory S. Paul estimated its length at 8 metres (26 ft), its weight at 1 tonne (2,200 lb).[6] The hands were unusually elongated, bearing sickle-shaped claws even more recurved than those of spinosaurids.[7]
Classification
The hand is quite distinct from other basal tetanurans, so it was not initially clear whether Megaraptor was an allosaurid, a carcharodontosaurid, a spinosauroid, or something else entirely.[3] Subsequent studies, as well as the identification of close relatives with similar large claws on the forelimbs (see below), helped identify Megaraptor as a highly advanced and lightly built allosauroid, and a member of the family Neovenatoridae.[8] More recent studies have proposed that Megaraptor and its kin are actually tyrannosauroids[9] or spinosauroids[10] as opposed to allosauroids.[9] A juvenile specimen described in 2014 has provided more evidence towards Megaraptor being a primitive tyrannosauroid.[11] The discovery of Gualicho indicates that Megaraptor may not be a tyrannosauroid, but either an allosauroid or basal coelurosaur.[12]
When first discovered and prior to publication, the spinosaurid Baryonyx was also reported to be a dromaeosaurid, and the allosauroid Chilantaisaurus was reported to be a possible spinosaurid, both based on the large hand claws.
The cladogram shown below follows an analysis by Porfiri et al., 2014.[1]
| Megaraptora |
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In the 2022 description of
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Paleoecology
Megaraptor is known from the Late
References
- ^ hdl:11336/12129.
- ^ .
- ^ a b Calvo, J. O.; Porfiri, J.D.; Veralli, C.; Novas, F.E.; Poblete, F. (2004). "Phylogenetic status of Megaraptor namunhuaiquii Novas based on a new specimen from Neuquén, Patagonia, Argentina". Ameghiniana. 41: 565–575.
- PMID 31827108.
- ^ "Just out | A new megaraptoran theropod dinosaur from the Upper Cretaceous Bajo de la Carpa Formation of northwestern Patagonia @ Cretaceous Research".
- ^ Paul, G.S., 2010, The Princeton Field Guide to Dinosaurs, Princeton University Press p. 99
- ^ Calvo, J.O., Porfiri, J.D., González-Riga, B.J., and Kellner, A.W. (2007) "A new Cretaceous terrestrial ecosystem from Gondwana with the description of a new sauropod dinosaur". Anais da Academia Brasileira de Ciências, 79(3): 529–41.[1]
- S2CID 22646156.
- ^ a b F. E. Novas; F. L. Agnolín; M. D. Ezcurra; J. I. Canale; J. D. Porfiri (2012). "Megaraptorans as members of an unexpected evolutionary radiation of tyrant-reptiles in Gondwana". Ameghiniana. 49 (Suppl): R33.
- ISBN 978-0-375-82419-7.
- hdl:11336/12129.)
{{cite journal}}: CS1 maint: multiple names: authors list (link - PMID 27410683.
- PMID 35474310.
- S2CID 252097368.
