Microraptoria (Greek, μίκρος, mīkros: "small"; Latin, raptor: "one who seizes") is a clade of basal dromaeosauridtheropoddinosaurs. The first microraptorians appeared 125 million years ago in China. Many are known for long feathers on their legs and may have been semiarboreal powered fliers, some of which were even capable of launching from the ground.[2] Most microraptorians were relatively small; adult specimens of Microraptor range between 77–90 centimetres long (2.53–2.95 ft) and weigh up to 1 kg (2.2 lb), making them some of the smallest known nonavialan dinosaurs.[3][4]
Microraptorians were a group of basal dromaeosaurids (popularly known as "raptors") with slender proportions and long limbs. With the exception of Hesperonychus from the late Cretaceous of North America, all microraptorians have been found in the Yixian and Jifuotang Formations of Liaoning County, China, hence why microraptorians are sometimes referred to as "Liaoning dromaeosaurs". These formations (collectively known as the Jehol group) have been dated to the early Cretaceous and at that time would have been part of a temperate wetland ecosystem threatened by frequent volcanic eruptions. Like other dromaeosaurids, microraptorians were carnivores with relatively large, serrated teeth and a hyperextendable second toe equipped with a curved claw.
Size and proportionsedit
A life restoration of Changyuraptor, a large "four-winged" microraptorine
Most microraptorians were small dinosaurs, with taxa such as Microraptor and especially Zhongjianosaurus being among the smallest nonavian dinosaurs known. However, some microraptorians, such as Tianyuraptor and Changyuraptor, were larger and similar to other dromaeosaurids in size. Many microraptorians also had long and robust arms and legs, in contrast to the stockier eudromaeosaurs, although long arms are not universal to the group, since the basal microraptorian Tianyuraptor had unusually short arms by dromaeosaurid standards.[5] Considering this, the small size and long wings of some microraptorians likely are examples of convergent evolution with other small paravians and early birds such as Anchiornis and Archaeopteryx.
Feathersedit
The fossilization conditions of the Jehol group are very accommodating to the preservation of soft structures in fossils, and as a result, many microraptorians have been preserved with a covering of feathers. Not only have long, advanced feathers been preserved on the arms and tails of many specimens, but a few species even have long feathers on their legs. This condition has also been seen in other paravians such as Anchiornis, and has caused these kinds of dinosaurs to be labelled as "four-winged dinosaurs". The largest known "four-winged" dinosaur, Changyuraptor, is a microraptorian. Some microraptorians such as Microraptor possibly were able to use these wings to glide or take off from the ground.[6][2]
Microraptoria is usually classified as a clade of dromaeosaurids. Senter and colleagues expressly coined the name without the subfamily suffix -inae to avoid perceived issues with erecting a traditional family-group taxon, should the group be found to lie outside the Dromaeosauridae proper.[8] Sereno offered a revised definition of the subgroup containing Microraptor to ensure that it would fall within the Dromaeosauridae, and erected the subfamily Microraptorinae, attributing it to Senter et al., though this usage has only appeared on his online TaxonSearch database and has not been formally published.[9]
The cladogram below follows a 2012 analysis by paleontologists Phil Senter, James I. Kirkland, Donald D. DeBlieux, Scott Madsen and Natalie Toth.[10]
^. Archived from the original on 2017-04-11. Retrieved 2017-04-11.
^ abDececchi, TA; Larsson, HC; Habib, MB (2016). "The wings before the bird: an evaluation of flapping-based locomotory hypotheses in bird antecedents". PeerJ. 4: e2159. doi:10.7717/peerj.2159. PMC4941780. PMID 27441115..
^Holtz, Thomas R. Jr. (2011) Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages, Winter 2010 Appendix.
^Chatterjee, S.; Templin, R.J. (2007). "Biplane wing planform and flight performance of the feathered dinosaur Microraptor gui" (PDF). Proceedings of the National Academy of Sciences. 104 (5): 1576–1580. Bibcode:2007PNAS..104.1576C. doi:10.1073/pnas.0609975104. PMC1780066. PMID 17242354.
^ abZheng, Xiaoting; Xu, Xing; You, Hailu; Zhao, Qi; Dong, Zhiming (2010-01-22). "A short-armed dromaeosaurid from the Jehol Group of China with implications for early dromaeosaurid evolution". Proceedings of the Royal Society of London B: Biological Sciences. 277 (1679): 211–217. doi:10.1098/rspb.2009.1178. ISSN 0962-8452. PMC2842677. PMID 19692406.
^Han, Gang; Chiappe, Luis M.; Ji, Shu-An; Habib, Michael; Turner, Alan H.; Chinsamy, Anusuya; Liu, Xueling; Han, Lizhuo (2014-07-15). "A new raptorial dinosaur with exceptionally long feathering provides insights into dromaeosaurid flight performance". Nature Communications. 5: ncomms5382. Bibcode:2014NatCo...5.4382H. doi:10.1038/ncomms5382. PMID 25025742.
^Longrich, Nicholas R.; Currie, Philip J. (2009-03-31). "A microraptorine (Dinosauria–Dromaeosauridae) from the Late Cretaceous of North America". Proceedings of the National Academy of Sciences. 106 (13): 5002–5007. Bibcode:2009PNAS..106.5002L. doi:10.1073/pnas.0811664106. ISSN 0027-8424. PMC2664043. PMID 19289829.
^Senter, Phil; Barsbold, R.; Britt, Brooks B.; Burnham, David B. (2004). "Systematics and evolution of Dromaeosauridae (Dinosauria, Theropoda)". Bulletin of the Gunma Museum of Natural History. 8: 1–20.
^Sereno, P. C. 2005. Stem Archosauria—TaxonSearch 2009-01-15 at the Wayback Machine [version 1.0, November 7, 2005
^Senter, P.; Kirkland, J. I.; Deblieux, D. D.; Madsen, S.; Toth, N. (2012). Dodson, Peter (ed.). "New Dromaeosaurids (Dinosauria: Theropoda) from the Lower Cretaceous of Utah, and the Evolution of the Dromaeosaurid Tail". PLOS ONE. 7 (5): e36790. Bibcode:2012PLoSO...736790S. doi:10.1371/journal.pone.0036790. PMC3352940. PMID 22615813.
"Expand and Life history of a basal bird: morphometrics of the Early Cretaceous Confuciusornis" Luis M Chiappe, Jesús Marugán-Lobón, Shu'an Ji & Zhonghe Zhou (2008)
Wikispecies has information related to Microraptoria.
December 15, 2023
microraptoria, greek, μίκρος, mīkros, small, latin, raptor, seizes, clade, basal, dromaeosaurid, theropod, dinosaurs, first, microraptorians, appeared, million, years, china, many, known, long, feathers, their, legs, have, been, semiarboreal, powered, fliers, . Microraptoria Greek mikros mikros small Latin raptor one who seizes is a clade of basal dromaeosaurid theropod dinosaurs The first microraptorians appeared 125 million years ago in China Many are known for long feathers on their legs and may have been semiarboreal powered fliers some of which were even capable of launching from the ground 2 Most microraptorians were relatively small adult specimens of Microraptor range between 77 90 centimetres long 2 53 2 95 ft and weigh up to 1 kg 2 2 lb making them some of the smallest known nonavialan dinosaurs 3 4 MicroraptoriansTemporal range 125 76 5 Ma PreꞒ Ꞓ O S D C P T J K Pg N Possible Late Maastrichtian recordFossil specimen of a Microraptor with white arrows pointing at preserved feathersScientific classificationDomain EukaryotaKingdom AnimaliaPhylum ChordataClade DinosauriaClade SaurischiaClade TheropodaFamily DromaeosauridaeClade MicroraptoriaSenter et al 2004Genera Changyuraptor Graciliraptor Hesperonychus Microraptor Shanag Sinornithosaurus Tianyuraptor Wulong Zhongjianosaurus 1 SynonymsMicroraptorinae Senter et al 2004 Microraptorini Senter et al 2004 Contents 1 Description 1 1 Size and proportions 1 2 Feathers 1 3 Characteristic features 5 7 2 Classification 3 See also 4 References 5 External linksDescription edit nbsp NGMC 91 believed to be a juvenile specimen of SinornithosaurusMicroraptorians were a group of basal dromaeosaurids popularly known as raptors with slender proportions and long limbs With the exception of Hesperonychus from the late Cretaceous of North America all microraptorians have been found in the Yixian and Jifuotang Formations of Liaoning County China hence why microraptorians are sometimes referred to as Liaoning dromaeosaurs These formations collectively known as the Jehol group have been dated to the early Cretaceous and at that time would have been part of a temperate wetland ecosystem threatened by frequent volcanic eruptions Like other dromaeosaurids microraptorians were carnivores with relatively large serrated teeth and a hyperextendable second toe equipped with a curved claw Size and proportions edit nbsp A life restoration of Changyuraptor a large four winged microraptorineMost microraptorians were small dinosaurs with taxa such as Microraptor and especially Zhongjianosaurus being among the smallest nonavian dinosaurs known However some microraptorians such as Tianyuraptor and Changyuraptor were larger and similar to other dromaeosaurids in size Many microraptorians also had long and robust arms and legs in contrast to the stockier eudromaeosaurs although long arms are not universal to the group since the basal microraptorian Tianyuraptor had unusually short arms by dromaeosaurid standards 5 Considering this the small size and long wings of some microraptorians likely are examples of convergent evolution with other small paravians and early birds such as Anchiornis and Archaeopteryx Feathers edit The fossilization conditions of the Jehol group are very accommodating to the preservation of soft structures in fossils and as a result many microraptorians have been preserved with a covering of feathers Not only have long advanced feathers been preserved on the arms and tails of many specimens but a few species even have long feathers on their legs This condition has also been seen in other paravians such as Anchiornis and has caused these kinds of dinosaurs to be labelled as four winged dinosaurs The largest known four winged dinosaur Changyuraptor is a microraptorian Some microraptorians such as Microraptor possibly were able to use these wings to glide or take off from the ground 6 2 Characteristic features 5 7 edit Microraptorines can be distinguished from other dromaeosaurids by these features A maxilla laterally sculpted by small pits A very short manual phalanx III 2 A shortened first digit of the hand A splatulate rounded pubic symphysis A metatarsal III with a pinched proximal end A slender metatarsal IIIn addition several features are present in microraptorines with the exception of Tianyuraptor which is believed to be a basal member of the clade A large oval fenestra in the coracoid Significantly shortened penultimate manual phalanges The posterior end of the ilium extending ventral to the ischial peduncle Lateral projections halfway down the pubis A strongly anteriorly curved pubic shaftClassification edit nbsp Artist s reconstruction of MicroraptorMicroraptoria is usually classified as a clade of dromaeosaurids Senter and colleagues expressly coined the name without the subfamily suffix inae to avoid perceived issues with erecting a traditional family group taxon should the group be found to lie outside the Dromaeosauridae proper 8 Sereno offered a revised definition of the subgroup containing Microraptor to ensure that it would fall within the Dromaeosauridae and erected the subfamily Microraptorinae attributing it to Senter et al though this usage has only appeared on his online TaxonSearch database and has not been formally published 9 The cladogram below follows a 2012 analysis by paleontologists Phil Senter James I Kirkland Donald D DeBlieux Scott Madsen and Natalie Toth 10 Dromaeosauridae XiaotingiaUnenlagiinaeShanagEudromaeosauria SaurornitholestinaeVelociraptorinaeDromaeosaurinaeMicroraptoria TianyuraptorHesperonychusMicroraptor sp Microraptor guiMicroraptor zhaoianusCryptovolansGraciliraptorSinornithosaurusSee also editTimeline of dromaeosaurid researchReferences edit 辽西下白垩统热河群一新微型驰龙类恐龙和热河生物群驰龙类的生态位分化 中国科学院古脊椎动物与古人类研究所 Archived from the original on 2017 04 11 Retrieved 2017 04 11 a b Dececchi TA Larsson HC Habib MB 2016 The wings before the bird an evaluation of flapping based locomotory hypotheses in bird antecedents PeerJ 4 e2159 doi 10 7717 peerj 2159 PMC 4941780 PMID 27441115 Holtz Thomas R Jr 2011 Dinosaurs The Most Complete Up to Date Encyclopedia for Dinosaur Lovers of All Ages Winter 2010 Appendix Chatterjee S Templin R J 2007 Biplane wing planform and flight performance of the feathered dinosaur Microraptor gui PDF Proceedings of the National Academy of Sciences 104 5 1576 1580 Bibcode 2007PNAS 104 1576C doi 10 1073 pnas 0609975104 PMC 1780066 PMID 17242354 a b Zheng Xiaoting Xu Xing You Hailu Zhao Qi Dong Zhiming 2010 01 22 A short armed dromaeosaurid from the Jehol Group of China with implications for early dromaeosaurid evolution Proceedings of the Royal Society of London B Biological Sciences 277 1679 211 217 doi 10 1098 rspb 2009 1178 ISSN 0962 8452 PMC 2842677 PMID 19692406 Han Gang Chiappe Luis M Ji Shu An Habib Michael Turner Alan H Chinsamy Anusuya Liu Xueling Han Lizhuo 2014 07 15 A new raptorial dinosaur with exceptionally long feathering provides insights into dromaeosaurid flight performance Nature Communications 5 ncomms5382 Bibcode 2014NatCo 5 4382H doi 10 1038 ncomms5382 PMID 25025742 Longrich Nicholas R Currie Philip J 2009 03 31 A microraptorine Dinosauria Dromaeosauridae from the Late Cretaceous of North America Proceedings of the National Academy of Sciences 106 13 5002 5007 Bibcode 2009PNAS 106 5002L doi 10 1073 pnas 0811664106 ISSN 0027 8424 PMC 2664043 PMID 19289829 Senter Phil Barsbold R Britt Brooks B Burnham David B 2004 Systematics and evolution of Dromaeosauridae Dinosauria Theropoda Bulletin of the Gunma Museum of Natural History 8 1 20 Sereno P C 2005 Stem Archosauria TaxonSearch Archived 2009 01 15 at the Wayback Machine version 1 0 November 7 2005 Senter P Kirkland J I Deblieux D D Madsen S Toth N 2012 Dodson Peter ed New Dromaeosaurids Dinosauria Theropoda from the Lower Cretaceous of Utah and the Evolution of the Dromaeosaurid Tail PLOS ONE 7 5 e36790 Bibcode 2012PLoSO 736790S doi 10 1371 journal pone 0036790 PMC 3352940 PMID 22615813 Expand and Life history of a basal bird morphometrics of the Early Cretaceous Confuciusornis Luis M Chiappe Jesus Marugan Lobon Shu an Ji amp Zhonghe Zhou 2008 External links edit1 http www paleodb org cgi bin bridge pl a basicTaxonInfo amp taxon no 143267 2 http www taxonsearch org dev taxon edit php tax id 483 amp Action View 3 http theropoddatabase blogspot com 2010 03 article 1311 means lewisuchinaeidae is html nbsp Wikispecies has information related to Microraptoria Retrieved from https en wikipedia org w index php title Microraptoria amp oldid 1171169020, wikipedia, wiki, book, books, library,
