Timeline of therizinosaur research

Last updated

Reconstructed skeleton of the therizinosaurs Falcarius utahensis and Nothronychus graffami Nothronychus graffami and Falcarius utahensis - Natural History Museum of Utah - DSC07207.JPG
Reconstructed skeleton of the therizinosaurs Falcarius utahensis and Nothronychus graffami

The timeline of therizinosaur research is a chronological listing of events in the history of paleontology focused on therizinosaurs. They were unusually long-necked, pot-bellied, and large-clawed herbivorous theropods most closely related to birds. The early history of therizinosaur research occurred in three phases. The first phase was the discovery of scanty and puzzling fossils in Asia by the Central Asiatic Expeditions of the 1920s and Soviet-backed research in the 1950s. This phase resulted in the discovery of the Therizinosaurus cheloniformis type specimen. Soviet paleontologist Evgeny Maleev interpreted these unusual remains as belonging to some kind of gigantic turtle.

Contents

The second major phase of therizinosaur research followed the discovery of better preserved remains in the 1970s by collaborative research between the Soviets and Mongolians. These finds revealed the true nature of therizinosaurs as bizarre dinosaurs. However, the exact nature and classification of therizinosaurs within Dinosauria was controversial as was their paleobiology. When Rozhdestventsky first reinterpreted therizinosaurs as dinosaurs he argued that they were unusual theropods that may have used their clawed arms to break open termite mounds or collect fruit. Osmolska and Roniewicz also considered therizinosaurs to be theropods.

In 1979, Altangerel Perle named the new species Segnosaurus galbinensis , which although he recognized was an unusual theropod, he did not recognize as a therizinosaur. Consequently, he named the new family Segnosauridae and, in 1980, Segnosauria. Two years later, Perle recognized commonalities between Therizinosaurus and segnosaurs, reclassifying the former as a member of the latter. From hereout therizinosaur research was considered "segnosaur" research. Perle himself thought that his "segnosaurs" were semi-aquatic fish-eaters. However, in the early 1990s, researchers like Rinchen Barsbold and Teresa Maryańska cast doubt on the connection between therizinosaurs and segnosaurs altogether.

Nevertheless, the description Alxasaurus elsitaiensis provided more evidence for a close relationship between the therizinosaurs and "segnosaurs" and led to a revision of their classification. The discovery of this and other primitive therizinosaurs in China formed the beginnings of the third major wave of therizinosaur research. That same year Russell and Russell reinterpreted therizinosaurs as herbivorous foragers like mammalian chalicotherium. Other significant finds of the 1990s include therizinosaur eggs with embryos preserved inside and the first known therizinosaur with feathers, Beipiaosaurus , which was described from China in 1999.

20th century

1950s

Holotype claw cast of Therizinosaurus Therizinosaurus clawcast aus.jpg
Holotype claw cast of Therizinosaurus

1954

1960s

1964

1970s

Referred arms to Therizinosaurus by Barsbold Therizinosaurus.jpg
Referred arms to Therizinosaurus by Barsbold

1970

1976

Segnosaurus holotype pelvis and metatarsus Segnosaurus holotype.png
Segnosaurus holotype pelvis and metatarsus

1979

1980s

Erlikosaurus holotype skull and feet Erlikosaurus skull and foot.jpg
Erlikosaurus holotype skull and feet
Enigmosaurus holotype pelvis Enigmosaurus.jpg
Enigmosaurus holotype pelvis
Claws initially identified as Alectrosaurus AMNH 6368 Therizinosaur.png
Claws initially identified as Alectrosaurus
Prosauropod-like restoration of Erlikosaurus Erlikosaurus.jpg
Prosauropod-like restoration of Erlikosaurus

1980

1981

1982

1983

1984

1986

1989

1990s

1990

1992

Skeletal composite of Alxasaurus specimens Alxasaurus elesitaiensis.jpg
Skeletal composite of Alxasaurus specimens

1993

Erlikosaurus skull scheme Schematic Erlikosaurus skull.png
Erlikosaurus skull scheme

1994

1995

1996

1997

1998

Left arm feather impressions from the Beipiaosaurus holotype Beipiaosaurus-Paleozoological Museum of China.jpg
Left arm feather impressions from the Beipiaosaurus holotype

1999

21st century

2000s

2000

Holotype elements from N. mckinleyi Nothronychus mckinleyi.jpg
Holotype elements from N. mckinleyi
Holotype dentary of Eshanosaurus Eshanosaurus.png
Holotype dentary of Eshanosaurus
Holotype braincase of N. mckinleyi Nothronychus braincase.png
Holotype braincase of N. mckinleyi
Pectoral girdle of Falcarius Falcarius chest region salt lake city.jpg
Pectoral girdle of Falcarius

2001

2002

2003

2004

2005

2006

2007

Embryonic therizinosaurid based on Nanchao embryos THERIZINOSAURUS.jpg
Embryonic therizinosaurid based on Nanchao embryos

2008

2009

2010s

Skeletal composite of therizinosaurs (not to scale) Therizinosaur skeletons.jpg
Skeletal composite of therizinosaurs (not to scale)

2010

2011

Reconstructed brain of Erlikosaurus Erlikosaurus cranial endocast.png
Reconstructed brain of Erlikosaurus
Skeletal restoration of Jianchangosaurus Jianchangosaurus.png
Skeletal restoration of Jianchangosaurus
Highlighted remains of N. mckinleyi and N. graffami Nothronychus sp. skeletal reconstruction.png
Highlighted remains of N. mckinleyi and N. graffami
Segnosaurus holotype mandible in lateral and inner views Segnosaurus hemimandible.jpg
Segnosaurus holotype mandible in lateral and inner views

2012

2013

2014

2015

2016

2017

Reconstructed brain of 'N. mckinleyi Nothronychus mckinleyi basicranial soft tissues.png
Reconstructed brain of 'N. mckinleyi

2018

2019

Lingyuanosaurus hand unguals Lingyuanosaurus manual unguals.png
Lingyuanosaurus hand unguals

2020s

2020

2021

Fukuivenator restored as a primitive therizinosaur Fukuivenator (Therizinosauria).png
Fukuivenator restored as a primitive therizinosaur

2022

Life reconstruction of Paralitherizinosaurus Paralitherizinosaurus Restoration.png
Life reconstruction of Paralitherizinosaurus

2023

See also

Related Research Articles

<i>Segnosaurus</i> Extinct genus of therizinosaurid dinosaur from late Cretaceous

Segnosaurus is a genus of therizinosaurid dinosaur that lived in what is now southeastern Mongolia during the Late Cretaceous, about 102–86 million years ago. Multiple incomplete but well-preserved specimens were discovered in the Gobi Desert in the 1970s, and in 1979 the genus and species Segnosaurus galbinensis were named. The generic name Segnosaurus means "slow lizard" and the specific name galbinensis refers to the Galbin region. The known material of this dinosaur includes the lower jaw, neck and tail vertebrae, the pelvis, shoulder girdle, and limb bones. Parts of the specimens have gone missing or become damaged since they were collected.

<i>Therizinosaurus</i> Therizinosaurid genus from the Late Cretaceous period

Therizinosaurus is a genus of very large therizinosaurid that lived in Asia during the Late Cretaceous period in what is now the Nemegt Formation around 70 million years ago. It contains a single species, Therizinosaurus cheloniformis. The first remains of Therizinosaurus were found in 1948 by a Mongolian field expedition at the Gobi Desert and later described by Evgeny Maleev in 1954. The genus is only known from a few bones, including gigantic manual unguals, from which it gets its name, and additional findings comprising fore and hindlimb elements that were discovered from the 1960s through the 1980s.

<span class="mw-page-title-main">Maniraptora</span> Clade of dinosaurs

Maniraptora is a clade of coelurosaurian dinosaurs which includes the birds and the non-avian dinosaurs that were more closely related to them than to Ornithomimus velox. It contains the major subgroups Avialae, Dromaeosauridae, Troodontidae, Oviraptorosauria, and Therizinosauria. Ornitholestes and the Alvarezsauroidea are also often included. Together with the next closest sister group, the Ornithomimosauria, Maniraptora comprises the more inclusive clade Maniraptoriformes. Maniraptorans first appear in the fossil record during the Jurassic Period, and survive today as living birds.

<i>Beipiaosaurus</i> Extinct genus of dinosaurs

Beipiaosaurus is a genus of therizinosauroid theropod dinosaurs that lived in Asia during the Early Cretaceous in the Yixian Formation. The first remains were found in 1996 and formally described in 1999. Before the discovery of Yutyrannus, Beipiaosaurus were among the heaviest dinosaurs known from direct evidence to be feathered. Beipiaosaurus is known from three reported specimens. Numerous impressions of feather structures were preserved that allowed researchers to determine the feathering color which turned out to be brownish.

<i>Falcarius</i> Extinct genus of therizinosaur dinosaur from the Early Cretaceous

Falcarius is a genus of primitive therizinosaur dinosaur that lived during the Early Cretaceous period in what is now North America. Its remains were first collected in the Cedar Mountain Formation in 1999, with subsequent findings made during the 2000s. The genus is known from multiple specimens ranging from immature to fully-grown individuals.

<span class="mw-page-title-main">Therizinosauria</span> Extinct clade of dinosaurs

Therizinosaurs were large herbivorous theropod dinosaurs whose fossils have been found across the Middle Jurassic to Late Cretaceous deposits in Europe, Asia and North America. Various features of the forelimbs, skull and pelvis unite these finds as both theropods and maniraptorans, making them relatives of birds. The name of the representative genus, Therizinosaurus, is derived from the Greek θερίζω and σαῦρος. The older representative, Segnosaurus, is derived from the Latin sēgnis ('slow') and the Greek σαῦρος.

<i>Nothronychus</i> Extinct genus of dinosaurs

Nothronychus is a genus of therizinosaurid theropod dinosaurs that lived in North America during the Late Cretaceous period. The type species, Nothronychus mckinleyi, was described by James Kirkland and Douglas G. Wolfe in 2001. It was recovered near New Mexico's border with Arizona, in an area known as the Zuni Basin, from rocks assigned to the Moreno Hill Formation, dating to the late Cretaceous period, around 92 million years ago. A second specimen, described in 2009 as a second species, Nothronychus graffami, was found in the Tropic Shale of Utah, dating to the early Turonian, between one million and a half million years older than N. mckinleyi.

<i>Enigmosaurus</i> Extinct genus of reptiles

Enigmosaurus is a genus of therizinosauroid that lived in Asia during the Late Cretaceous period. It was a medium-sized, ground-dwelling, bipedal herbivore that represents the third therizinosaur taxon from the Bayan Shireh Formation, although it is known from the lower part. The genus is monotypic, including only the type species E. mongoliensis, known from a well preserved pelvis and other tentative body remains.

<i>Garudimimus</i> Ornithomimosaur genus from the Late Cretaceous

Garudimimus is a genus of ornithomimosaur that lived in Asia during the Late Cretaceous. The genus is known from a single specimen found in 1981 by a Soviet-Mongolian paleontological expedition in the Bayan Shireh Formation and formally described in the same year by Rinchen Barsbold; the only species is Garudimimus brevipes. Several interpretations about the anatomical traits of Garudimimus were made in posterior examinations of the specimen, but most of them were criticized during its comprehensive redescription in 2005. Extensive undescribed ornithomimosaur remains at the type locality of Garudimimus may represent additional specimens of the genus.

<i>Alxasaurus</i> Therizinosauroid dinosaur genus from the Early Cretaceous

Alxasaurus is a genus of therizinosauroid theropod dinosaurs from the Early Cretaceous Bayin-Gobi Formation of Inner Mongolia.

<span class="mw-page-title-main">Therizinosauridae</span> Extinct family of dinosaurs

Therizinosauridae is a family of derived (advanced) therizinosauroid dinosaurs whose fossil remains have been found in mostly Late Cretaceous boundary. Even though representative fossils have only been found throughout Asia and North America, the range of Therizinosauridae is believed to have spanned much of the supercontinent of Laurasia based on several footprints and isolated remains in Europe and Africa. Currently, Therizinosauridae comprises eight described and named taxa.

<span class="mw-page-title-main">Bayan Shireh Formation</span> Geological formation in Mongolia

The Bayan Shireh Formation is a geological formation in Mongolia, that dates to the Cretaceous period. It was first described and established by Vasiliev et al. 1959.

<i>Erliansaurus</i> Extinct genus of dinosaurs

Erliansaurus is a genus of therizinosaur theropod dinosaur that lived in Asia during the Cenomanian stage of the Late Cretaceous period in what is now Nei Mongol, Iren Dabasu Formation.

<i>Erlikosaurus</i> Extinct genus of therizinosaurid dinosaur from the Late Cretaceous

Erlikosaurus is a genus of therizinosaurid that lived in Asia during the Late Cretaceous period. The fossils, a skull and some post-cranial fragments, were found in the Bayan Shireh Formation of Mongolia in 1972, dating to around 96 million and 89 million years ago. These remains were later described by Altangerel Perle and Rinchen Barsbold in 1980, naming the new genus and species Erlikosaurus andrewsi. It represents the second therizinosaur taxon from this formation with the most complete skull among members of this peculiar family of dinosaurs.

Eshanosaurus is a genus of a dinosaur from the early Jurassic Period. It is known only from a fossil partial lower jawbone, found in China. It may be a therizinosaurian, and if so the earliest known coelurosaur.

<i>Neimongosaurus</i> Extinct genus of dinosaurs

Neimongosaurus is a genus of herbivorous therizinosaur theropod dinosaur that lived in Asia during the Cenomanian stage of the Late Cretaceous period in what is now the Iren Dabasu Formation.

<i>Nanshiungosaurus</i> Extinct genus of reptiles

Nanshiungosaurus is a genus of therizinosaurid that lived in what is now Asia during the Late Cretaceous of South China. The type species, Nanshiungosaurus brevispinus, was first discovered in 1974 and described in 1979 by Dong Zhiming. It is represented by a single specimen preserving most of the cervical and dorsal vertebrae with the pelvis. A supposed and unlikely second species, "Nanshiungosaurus" bohlini, was found in 1992 and described in 1997. It is also represented by vertebrae but this species however, differs in geological age and lacks authentic characteristics compared to the type, making its affinity to the genus unsupported.

<i>Suzhousaurus</i> Extinct genus of dinosaurs

Suzhousaurus is a genus of large therizinosauroid dinosaur from the Early Cretaceous of China. The genus is known from two specimens discovered on the Xiagou Formation and Zhonggou Formation—which are situated in the Xinminbao Group. These findings were made during field-works in 1999 and 2004. Though Suzhousaurus is known from these two specimens, an earlier named and described therizinosauroid from the adjacent basin, "Nanshiungosaurus" bohlini, may be synonymous with the former. However, Suzhousaurus can not be compared to this species due to non-overlapping material and the loss of the same. Moreover, this synonymy will result in Suzhousaurus bohlini with "N". bohlini having priority.

<i>Martharaptor</i> Extinct genus of dinosaurs

Martharaptor is a genus of therizinosauroid theropod dinosaurs from the Early Cretaceous of the Cedar Mountain Formation in Utah. They can be distinguished from other therizinosauroids by means of several features of the skeleton which were intermediate between early therizinosaurs such as Falcarius and Beipiaosaurus, and more "advanced" members of the group like therizinosaurids. The deep and homogeneous hand claws clearly differ from the case in early therizinosauroids, but the foot has not yet acquired the robust morphology of therizinosaurids.

Lindsay E. Zanno is an American vertebrate paleontologist and a leading expert on theropod dinosaurs and Cretaceous paleoecosystems. She is the Head of Paleontology at the North Carolina Museum of Natural Sciences and an Associate Research Professor in the Department of Biological Sciences at North Carolina State University.

References

  1. Maleev, E. A. (1954). "Новый черепахообразный ящер в Монголии" [New turtle like reptile in Mongolia]. Priroda (3): 106−108. Translated paper
  2. Zakharov, S. A. (1964). "О сеноманском динозавре, следы которого обнаружены в долине р.Ширкент" [On the Cenomanian dinosaur, the tracks of which were found in the Shirkent River Valley]. In Reiman, V. M. (ed.). Paleontology of Tajikistan (in Russian). Dushanbe: Academy of Sciences of Tajik S.S.R. Press. pp. 31−35.
  3. Rozhdestvensky, A. K. (1970). "О гигантских когтевых фалангах загадочных рептилий мезозоя" [Giant claws of enigmatic Mesozoic reptiles]. Paleontological Journal (in Russian). 1970 (1): 131−141.
  4. Osmólska, H.; Roniewicz, E. (1970). "Deinocheiridae, a new family of theropod dinosaurs" (PDF). Palaeontologica Polonica (21): 5−19. Archived from the original (PDF) on 2016-03-03. Retrieved 2020-08-18.
  5. Barsbold, R. (1976). "On the evolution and systematics of the late Mesozoic dinosaurs". Trudy – Sovmestnaya Sovetsko-Mongol'skaya Paleontologicheskaya Ekspeditsiya (in Russian). 3: 68–75.
  6. Barsbold, R. (1976). "Новые данные о теризинозавре (Therizinosauridae, Theropoda)" [New data on Therizinosaurus (Therizinosauridae, Theropoda)]. In Kramarenko, N. N.; Luvsandansan, B.; Voronin, Y. I.; Barsbold, R.; Rozhdestvensky, A. K.; Trofimov, B. A.; Reshetov, V. Y. (eds.). Paleontology and Biostratigraphy of Mongolia. The Joint Soviet-Mongolian Paleontological Expedition, Transactions. Moscow: Nauka Press. pp. 76−92.
  7. Dong, Z. (1979). "Cretaceous dinosaur fossils in southern China" [Cretaceous dinosaurs of the Huanan (south China)]. In Institute of Vertebrate Paleontology and Paleoanthropology; Nanjing Institute of Paleontology (eds.). Mesozoic and Cenozoic Redbeds in Southern China (in Chinese). Beijing: Science Press. pp. 342−350. Translated paper
  8. Perle, A. (1979). "Segnosauridae - новое семейство позднемеловых хищных динозавров Монголии" [Segnosauridae - a new family of theropods from the Late Cretaceous of Mongolia]. Transactions of the Joint Soviet-Mongolian Paleontological Expedition (in Russian). 8: 45−55. Translated paper
  9. Barsbold, R.; Perle, A. (1980). "Segnosauria, a new suborder of carnivorous dinosaurs" (PDF). Acta Palaeontologica Polonica. 25 (2): 190−192.
  10. Perle, A. (1981). "Новый сегнозаврид из верхнего мела Монголии" [New segnosaurid from the Upper Cretaceous of Mongolia]. Transactions of the Joint Soviet-Mongolian Paleontological Expedition (in Russian). 15: 50−59. Translated paper
  11. Perle, A. (1982). "A hind limb of Therizinosaurus from the Upper Cretaceous of Mongolia". Problems in Mongolian Geology (in Russian). 5: 94−98. Translated paper
  12. Barsbold, R. (1983). "Хищные динозавры мела Монголии" [Carnivorous dinosaurs from the Cretaceous of Mongolia](PDF). Transactions of the Joint Soviet-Mongolian Paleontological Expedition (in Russian). 19: 89. Translated paper
  13. Paul, G. S. (1984). "The segnosaurian dinosaurs: relics of the prosauropod-ornithischian transition?". Journal of Vertebrate Paleontology. 4 (4): 507−515. Bibcode:1984JVPal...4..507P. doi:10.1080/02724634.1984.10012026. ISSN   0272-4634. JSTOR   4523011.
  14. Gauthier, J. (1986). "Saurischian monophyly and the origin of birds". Memoirs of the California Academy of Sciences. 8: 45. Archived from the original on 2019-08-16.
  15. Sereno, P. (1989). "Prosauropod monophyly and basal sauropodomorph phylogeny". Abstract of Papers. Forty-Ninth Annual Meeting Society of Vertebrate Paleontology. Journal of Vertebrate Paleontology. Vol. 9, no. 3 Supplement. p. 39A. ISSN   0272-4634. JSTOR   4523276.
  16. Mader, B. J.; Bradley, R. L. (1989). "A redescription and revised diagnosis of the syntypes of the Mongolian tyrannosaur Alectrosaurus olseni". Journal of Vertebrate Paleontology. 9 (1): 41–55. Bibcode:1989JVPal...9...41M. doi:10.1080/02724634.1989.10011737.
  17. Barsbold, R.; Maryańska, T. (1990). "Saurischia Sedis Mutabilis: Segnosauria". In Weishampel, D. B.; Osmolska, H.; Dodson, P. (eds.). The Dinosauria (1st ed.). Berkeley: University of California Press. pp. 408−415. ISBN   9780520067271.
  18. Norman, D. B. (1990). "Problematic Theropoda: Coelurosauria". In Weishampel, D. B.; Osmolska, H.; Dodson, P. (eds.). The Dinosauria (1st ed.). Berkeley: University of California Press. pp. 280−305. ISBN   9780520067271.
  19. Dong, Z. (1992). Dinosaurian Faunas of China. Beijing: China Ocean Press. p. 187. ISBN   3-540-52084-8.
  20. Russell, D. A.; Dong, Z. (1993). "The affinities of a new theropod from the Alxa Desert, Inner Mongolia, People's Republic of China". Canadian Journal of Earth Sciences. 30 (10): 2107−2127. Bibcode:1993CaJES..30.2107R. doi:10.1139/e93-183.
  21. Russell, D. A.; Russell, D. E. (1993). "Mammal-dinosaur convergence". National Geographic Research. 9: 70–79. ISSN   8755-724X.
  22. Clark, J. M.; Perle, A.; Norell, M. (1994). "The skull of Erlicosaurus andrewsi, a Late Cretaceous Segnosaur (Theropoda, Therizinosauridae) from Mongolia". American Museum Novitates (3115): 1−39. hdl: 2246/3712 .
  23. Nessov, L. A. (1995). Dinosaurs of northern Eurasia: new data about assemblages, ecology, and paleobiogeography (in Russian). Saint Petersburg: Institute of Earth Crust, Saint Petersburg University. p. 49. Translated paper
  24. Manning, T. W.; Joysey, K. A.; Cruickshank, A. R. I. (1997). "Observations of microstructures within dinosaur eggs from Henan Province, Peoples' Republic of China". In Wolberg, D. L.; Stump, E.; Rosenberg, R. D. (eds.). Dinofest International: Proceedings of a Symposium Held at Arizona State University. Pennsylvania: Academy of Natural Sciences. pp. 287−290.
  25. Dong, Z.; You, H. (1997). "A new segnosaur from Mazhongshan Area, Gansu Province, China". In Dong, Z. M. (ed.). Sino-Japanese Silk Road Dinosaur Expedition. Beijing: China Ocean Press. pp. 90−95.
  26. Russell, D. A. (1997). "Therizinosauria". In Currie, P. J.; Padian, K. (eds.). Encyclopedia of Dinosaurs. San Diego: Academic Press. pp. 729−730. ISBN   978-0-12-226810-6.
  27. Zhao, X.; Xu, X. (1998). "The oldest coelurosaurian". Nature. 394 (6690): 234–235. Bibcode:1998Natur.394..234Z. doi:10.1038/28300. S2CID   4424059.
  28. Xu, X.; Tang, Z.-L.; Wang, X. L. (1999). "A therizinosauroid dinosaur with integumentary structures from China". Nature. 339 (6734): 350−354. Bibcode:1999Natur.399..350X. doi:10.1038/20670. ISSN   1476-4687. S2CID   204993327.
  29. Carpener, K. (1999). "The Embryo and Hatching". Eggs, Nests, and Baby Dinosaurs: A Look at Dinosaur Reproduction (Life of the Past). Bloomington: Indiana University Press. p. 209. ISBN   9780253334978.
  30. Manning, T. W.; Joysey, K. A.; Cruickshank, A. R. I. (2000). "In ovo tooth replacement in a therizinosauroid dinosaur". In Bravo, A. M.; Reyes, T. (eds.). Extended Abstracts, First International Symposium on Dinosaur Eggs and Babies. Spain: Impremta Provincial de la Diputació Lleida, Isona i Conca Dellà. pp. 129−134.
  31. Xu, X.; Zhao, X.; Clark, J. M. (2001). "A new therizinosaur from the Lower Jurassic lower Lufeng Formation of Yunnan, China". Journal of Vertebrate Paleontology. 21 (3): 477−483. doi:10.1671/0272-4634(2001)021[0477:ANTFTL]2.0.CO;2. JSTOR   20061976. S2CID   131298010.
  32. Kirkland, J. I.; Wolfe, D. G. (2001). "First definitive therizinosaurid (Dinosauria; Theropoda) from North America". Journal of Vertebrate Paleontology. 21 (3): 410−414. doi:10.1671/0272-4634(2001)021[0410:fdtdtf]2.0.co;2. JSTOR   20061971. S2CID   85705529.
  33. Zhang, X.-H.; Xu, X.; Zhao, Z.-J.; Sereno, P. C.; Kuang, X.-W.; Tan, L. (2001). "A long-necked therizinosauroid dinosaur from the Upper Cretaceous Iren Dabasu Formation of Nei Mongol, People's Republic of China" (PDF). Vertebrata PalAsiatica. 39 (4): 282−290.
  34. Xu, X.; Zhang, Z.-H.; Sereno, P. C.; Zhao, X.-J.; Kuang, X.-W.; Han, J.; Tan, L. (2002). "A new therizinosauroid (Dinosauria, Theropoda) from the Upper Cretaceous Iren Dabasu Formation of Nei Mongol" (PDF). Vertebrata PalAsiatica. 40: 228−240.
  35. Xu, X.; Cheng, Y.; Wang, X.-L.; Chang, C. (2003). "Pygostyle‐like Structure from Beipiaosaurus (Theropoda, Therizinosauroidea) from the Lower Cretaceous Yixian Formation of Liaoning, China". Acta Geologica Sinica. 77 (3): 294–298. doi:10.1111/j.1755-6724.2003.tb00744.x. S2CID   128471217.
  36. Kirkland, J. I.; Zanno, L. E.; DeBlieux, D. D.; Sampson, S. D. (2004). "A new, basal-most therizinosauroid (Theropoda: Maniraptora) from Utah demonstrates a pan-Laurasian distribution for Early Cretaceous (Barremian) therizinosauroids". Journal of Vertebrate Paleontology. 24 (supp. 3): 78A. doi:10.1080/02724634.2004.10010643. S2CID   220415208.
  37. Smith, D. K.; Kirkland, J. I.; Sanders, R. K.; Zanno, L. E.; DeBlieux, D. D. (2004). "A comparison of North American therizinosaur (Theropoda: Dinosauria) braincases". Journal of Vertebrate Paleontology. 24 (supp. 3): 114A. doi:10.1080/02724634.2004.10010643. S2CID   220415208.
  38. Zanno, L. E. (2004). "The pectoral girdle and forelimb of a primitive therizinosauroid (Theropoda: Maniraptora): New information on the phylogenetics and evolution of therizinosaurs". Journal of Vertebrate Paleontology. 24 (supp. 3): 134A. doi:10.1080/02724634.2004.10010643. S2CID   220415208.
  39. Zanno, L. E. (2004). The Pectoral Girdle and Forelimb of a Primitive Therizinosauroid (Theropoda, Maniraptora) with Phylogenetic and Functional Implications (PhD diss.). Department of Geology and Geophysics, University of Utah.
  40. Kirkland, J. I.; Zanno, L. E.; Sampson, S. D.; Clark, J. M.; DeBlieux, D. D. (2005). "A primitive therizinosauroid dinosaur from the Early Cretaceous of Utah". Nature. 435 (7038): 84–87. Bibcode:2005Natur.435...84K. doi:10.1038/nature03468. PMID   15875020. S2CID   4428196.
  41. Zanno, L. E.; Erickson, G. M. (2006). "Ontogeny and life history of Falcarius utahensis, a primitive therizinosauroid from the Early Cretaceous of Utah". Journal of Vertebrate Paleontology. 26 (supp. 3): 143A. doi:10.1080/02724634.2006.10010069. S2CID   220413406.
  42. Zanno, L. E. (2006). "The pectoral girdle and forelimb of the primitive therizinosauroid Falcarius Utahensis (Theropoda, Maniraptora): analyzing evolutionary trends within Therizinosauroidea". Journal of Vertebrate Paleontology. 26 (3): 636−650. doi:10.1671/0272-4634(2006)26[636:tpgafo]2.0.co;2. JSTOR   4524610. S2CID   86166623.
  43. Burch, S. H. (2006). "The range of motion of the glenohumeral joint of the therizinosaur Neimongosaurus yangi (Dinosauria: Theropoda)". Journal of Vertebrate Paleontology. 26 (supp. 3): 46A. doi:10.1080/02724634.2006.10010069. S2CID   220413406.
  44. Sennikov, A. G. (2006). "Читая следы сегнозавров" [Reading segnosaur tracks]. Priroda (in Russian). 5: 58−67.
  45. Li, D.; Peng, C.; You, H.; Lamanna, M. C.; Harris, J. D.; Lacovara, K. J.; Zhang, J. (2007). "A Large Therizinosauroid (Dinosauria: Theropoda) from the Early Cretaceous of Northwestern China" (PDF). Acta Geologica Sinica (English Edition). 81 (4): 539–549. doi:10.1111/j.1755-6724.2007.tb00977.x. ISSN   1000-9515. S2CID   130262869.
  46. Kundrát, M.; Cruickshank, A. R. I.; Manning, T. W.; Nudds, J. (2007). "Embryos of therizinosauroid theropods from the Upper Cretaceous of China: diagnosis and analysis of ossification patterns". Acta Zoologica. 89 (3): 231−251. doi:10.1111/j.1463-6395.2007.00311.x.
  47. Li, D.; You, H.; Zhang, J. (2008). "A new specimen of Suzhousaurus megatherioides (Dinosauria: Therizinosauroidea) from the Early Cretaceous of northwestern China". Canadian Journal of Earth Sciences. 45 (7): 769–779. Bibcode:2008CaJES..45..769L. doi:10.1139/E08-021.
  48. Lee, Y.-N.; Barsbold, R.; Currie, P. J. (2008). "A short report of Korea-Mongolia International Dinosaur Project (1st and 2nd year)". Journal of Vertebrate Paleontology. 28 (supp. 003): 104A–105A. doi:10.1080/02724634.2008.10010459.
  49. Zanno, L. E.; Gillette, D. D.; Albright, L. B.; Titus, A. L. (2009). "A new North American therizinosaurid and the role of herbivory in predatory dinosaur evolution". Proceedings of the Royal Society B. 276 (1672): 3505−3511. doi: 10.1098/rspb.2009.1029 . JSTOR   30244145. PMC   2817200 . PMID   19605396.
  50. Barrett, P. M. (2009). "The affinities of the enigmatic dinosaur Eshanosaurus deguchiianus from the Early Jurassic of Yunnan Province, People's Republic of China". Palaeontology. 52 (4): 681−688. Bibcode:2009Palgy..52..681B. doi:10.1111/j.1475-4983.2009.00887.x.
  51. Xu, X.; Zheng, X.; You, H. (2009). "A new feather type in a nonavian theropod and the early evolution of feathers". Proceedings of the National Academy of Sciences. 106 (3): 832−834. doi: 10.1073/pnas.0810055106 . PMC   2630069 . PMID   19139401.
  52. Zanno, L. E. (2010). "Osteology of Falcarius utahensis (Dinosauria: Theropoda): characterizing the anatomy of basal therizinosaurs". Zoological Journal of the Linnean Society. 158 (1): 196–230. doi: 10.1111/j.1096-3642.2009.00464.x .
  53. Zanno, L. E. (2010). "A taxonomic and phylogenetic re-evaluation of Therizinosauria (Dinosauria: Maniraptora)". Journal of Systematic Palaeontology. 8 (4): 503−543. doi:10.1080/14772019.2010.488045. S2CID   53405097.
  54. Senter, P.; James, R. H. (2010). "Hip heights of the gigantic theropod dinosaurs Deinocheirus mirificus and Therizinosaurus cheloniformis, and implications for museum mounting and paleoecology" (PDF). Bulletin of Gunma Museum of Natural History (14): 1−10.
  55. Smith, D. K.; Zanno, L. E.; Sanders, R. K.; Deblieux, D. D.; Kirkland, J. I. (2011). "New information on the braincase of the North American therizinosaurian (Theropoda, Maniraptora) Falcarius utahensis". Journal of Vertebrate Paleontology. 31 (2): 387−404. Bibcode:2011JVPal..31..387S. doi:10.1080/02724634.2011.549442. JSTOR   25835833. S2CID   73715992.
  56. Zanno, L. E.; Makovicky, P. J. (2011). "Herbivorous ecomorphology and specialization patterns in theropod dinosaur evolution". Proceedings of the National Academy of Sciences. 108 (1): 232−237. Bibcode:2011PNAS..108..232Z. doi: 10.1073/pnas.1011924108 . PMC   3017133 . PMID   21173263.
  57. Qian, M.-P.; Zhang, Z.-Y.; Jiang, Y.; Jiang, Y.-G.; Zhang, Y.-J.; Chen, R.; Xing, G.-F. (2012). "浙江白垩纪镰刀龙类恐龙" [Cretaceous therizinosaurs in Zhejiang of eastern China]. Journal of Geology (in Chinese). 36 (4): 337−348.
  58. Lautenschlager, S.; Emily, J. R.; Perle, A.; Zanno, L. E.; Lawrence, M. W. (2012). "The Endocranial Anatomy of Therizinosauria and Its Implications for Sensory and Cognitive Function". PLOS ONE. 7 (12): e52289. Bibcode:2012PLoSO...752289L. doi: 10.1371/journal.pone.0052289 . PMC   3526574 . PMID   23284972.
  59. Senter, P.; Kirkland, J. I.; Deblieux, D. D. (2012). "Martharaptor greenriverensis, a New Theropod Dinosaur from the Lower Cretaceous of Utah". PLOS ONE. 7 (8): e43911. Bibcode:2012PLoSO...743911S. doi: 10.1371/journal.pone.0043911 . PMC   3430620 . PMID   22952806.
  60. Fiorillo, A. R.; Adams, T. L. (2012). "A Therizinosaur Track from the Lower Cantwell Formation (upper Cretaceous) of Denali National Park, Alaska". PALAIOS. 27 (6): 395−400. Bibcode:2012Palai..27..395F. doi:10.2110/palo.2011.p11-083r. S2CID   129517554.
  61. Lautenschlager, S. (2013). "Cranial myology and bite force performance of Erlikosaurus andrewsi : a novel approach for digital muscle reconstructions". Journal of Anatomy. 222 (2): 260−272. doi: 10.1111/joa.12000 . PMC   3632231 . PMID   23061752.
  62. Lautenschlager, S.; Witmer, L. M.; Perle, A.; Rayfield, E. J. (2013). "Edentulism, beaks, and biomechanical innovations in the evolution of theropod dinosaurs". PNAS. 110 (51): 20657−20662. Bibcode:2013PNAS..11020657L. doi: 10.1073/pnas.1310711110 . JSTOR   23761610. PMC   3870693 . PMID   24297877.
  63. Pu, H.; Kobayashi, Y.; Lü, J.; Xu, L.; Wu, Y.; Chang, H.; Zhang, J.; Jia, S. (2013). "An Unusual Basal Therizinosaur Dinosaur with an Ornithischian Dental Arrangement from Northeastern China". PLOS ONE. 8 (5): e63423. Bibcode:2013PLoSO...863423P. doi: 10.1371/journal.pone.0063423 . PMC   3667168 . PMID   23734177.
  64. Kobayashi, Y.; Lee, Y.; Barsbold, R.; Zelenitsky, D.; Tanaka, K. (2013). "First record of a dinosaur nesting colony from Mongolia reveals nesting behavior of therizinosauroids". In Maxwell, E.; Miller-Camp, J.; Anemone, R. (eds.). 73rd Annual Meeting of Society of Vertebrate Paleontology. Los Angeles. p. 155.{{cite book}}: CS1 maint: location missing publisher (link)
  65. Lautenschlager, S. (2014). "Morphological and functional diversity in therizinosaur claws and the implications for theropod claw evolution". Proceedings of the Royal Society B. 28 (1785): 20140497. doi: 10.1098/rspb.2014.0497 . PMC   4024305 . PMID   24807260.
  66. Li, Q.; Clarke, J. A.; Gao, K.-Q.; Zhou, C.-F.; Meng, Q.; Li, D.; D’Alba, L.; Shawkey, M. D. (2014). "Melanosome evolution indicates a key physiological shift within feathered dinosaurs". Nature. 507 (7492): 350−353. Bibcode:2014Natur.507..350L. doi:10.1038/nature12973. PMID   24522537. S2CID   4395833.
  67. Hedrick, B. P.; Zanno, L. E.; Wolfe, D. G.; Dodson, P. (2015). "The Slothful Claw: Osteology and Taphonomy of Nothronychus mckinleyi and N. graffami (Dinosauria: Theropoda) and Anatomical Considerations for Derived Therizinosaurids". PLOS ONE. 10 (6): e0129449. Bibcode:2015PLoSO..1029449H. doi: 10.1371/journal.pone.0129449 . PMC   4465624 . PMID   26061728.
  68. Smith, D. K. (2015). "Craniocervical Myology and Functional Morphology of the Small-Headed Therizinosaurian Theropods Falcarius utahensis and Nothronychus mckinleyi". PLOS ONE. 10 (2): e0117281. Bibcode:2015PLoSO..1017281S. doi: 10.1371/journal.pone.0117281 . PMC   4338109 . PMID   25706764.
  69. Kobayashi, Y.; Chinzorig, T.; Tsogtbaatar, K.; Barsbold, R. (2015). "A new therizinosaur with functionally didactyl hands from the Bayanshiree Formation (Cenomanian-Turonian), Omnogovi Province, southeastern Mongolia" (PDF). Journal of Vertebrate Paleontology. Program and Abstracts. Photographs
  70. Gierliński, G. D. (2015). "New Dinosaur Footprints from the Upper Cretaceous of Poland in the Light of Paleogeographic Context". Ichnos. 22 (3–4): 220−226. Bibcode:2015Ichno..22..220G. doi:10.1080/10420940.2015.1063489. S2CID   128598690.
  71. Zanno, L. E.; Tsogtbaatar, K.; Chinzorig, T.; Gates, T. A. (2016). "Specializations of the mandibular anatomy and dentition of Segnosaurus galbinensis (Theropoda: Therizinosauria)". PeerJ. 4: e1885. doi: 10.7717/peerj.1885 . PMC   4824891 . PMID   27069815.
  72. Sues, H.-D.; Averianov, A. (2016). "Therizinosauroidea (Dinosauria: Theropoda) from the Upper Cretaceous of Uzbekistan". Cretaceous Research. 59: 155−178. Bibcode:2016CrRes..59..155S. doi: 10.1016/j.cretres.2015.11.003 .
  73. Botelho, J. H.; Smith-Paredes, D.; Soto-Acuña, S.; Núñez-León, D.; Palma, V.; Vargas, A. O. (2016). "Greater Growth of Proximal Metatarsals in Bird Embryos and the Evolution of Hallux Position in the Grasping Foot". Journal of Experimental Zoology Part B: Molecular and Developmental Evolution. 328 (1–2): 106−118. doi:10.1002/jez.b.22697. hdl: 10533/232005 . ISSN   1552-5015. PMID   27649924. S2CID   4952929.
  74. Lautenschlager, S. (2017). "Functional niche partitioning in Therizinosauria provides new insights into the evolution of theropod herbivory" (PDF). Palaeontology. 60 (3): 375−387. Bibcode:2017Palgy..60..375L. doi:10.1111/pala.12289. S2CID   90965431.
  75. Masrour, M.; Lkebir, N.; Pérez-Lorente, F. (2017). "Anza palaeoichnological site. Late Cretaceous. Morocco. Part II. Problems of large dinosaur trackways and the first African Macropodosaurus trackway". Journal of African Earth Sciences. 134: 776−793. Bibcode:2017JAfES.134..776M. doi:10.1016/j.jafrearsci.2017.04.019. ISSN   1464-343X.
  76. Button, K.; You, H.; Kirkland, J. I.; Zanno, L. E. (2017). "Incremental growth of therizinosaurian dental tissues: implications for dietary transitions in Theropoda". PeerJ. 5: e4129. doi: 10.7717/peerj.4129 . PMC   5729821 . PMID   29250467.
  77. Smith, D. K.; Sanders, R. K.; Wolfe, D. G. (2018). "A re-evaluation of the basicranial soft tissues and pneumaticity of the therizinosaurian Nothronychus mckinleyi (Theropoda; Maniraptora)". PLOS ONE. 13 (7): e0198155. Bibcode:2018PLoSO..1398155S. doi: 10.1371/journal.pone.0198155 . PMC   6067709 . PMID   30063717.
  78. Fiorillo, A. R.; McCarthy, P. J.; Kobayashi, Y.; Tomsich, C. S.; Tykoski, R. S.; Lee, Y.-N.; Tanaka, T.; Noto, C. R. (2018). "An unusual association of hadrosaur and therizinosaur tracks within Late Cretaceous rocks of Denali National Park, Alaska". Scientific Reports. 8 (11706): 11706. Bibcode:2018NatSR...811706F. doi: 10.1038/s41598-018-30110-8 . PMC   6076232 . PMID   30076347.
  79. McNamara, M. E.; Zhang, F.; Kearns, S. L.; Orr, P. J.; Toulouse, A.; Foley, T.; Hone, D. W. E; Rogers, C. S.; Benton, M. J.; Johnson, D.; Xu, X.; Zhou, Z. (2018). "Fossilized skin reveals coevolution with feathers and metabolism in feathered dinosaurs and early birds". Nature Communications. 9 (2072): 2072. Bibcode:2018NatCo...9.2072M. doi: 10.1038/s41467-018-04443-x . ISSN   2041-1723. PMC   5970262 . PMID   29802246.
  80. Macaluso, L.; Tschopp, E.; Mannion, P. (2018). "Evolutionary changes in pubic orientation in dinosaurs are more strongly correlated with the ventilation system than with herbivory". Palaeontology. 61 (5): 703−719. Bibcode:2018Palgy..61..703M. doi:10.1111/pala.12362. S2CID   133643430.
  81. Hartman, S.; Mortimer, M.; Wahl, W. R.; Lomax, D. R.; Lippincott, J.; Lovelace, D. M. (2019). "A new paravian dinosaur from the Late Jurassic of North America supports a late acquisition of avian flight". PeerJ. 7: e7247. doi: 10.7717/peerj.7247 . PMC   6626525 . PMID   31333906.
  82. Xi Yao; Chun-Chi Liao; Corwin Sullivan; Xing Xu (2019). "A new transitional therizinosaurian theropod from the Early Cretaceous Jehol Biota of China". Scientific Reports. 9 (1): Article number 5026. Bibcode:2019NatSR...9.5026Y. doi:10.1038/s41598-019-41560-z. PMC   6430829 . PMID   30903000.
  83. Liao, C.-C.; Xu, X. (2019). "Cranial osteology of Beipiaosaurus inexpectus (Theropoda: Therizinosauria)". Vertebrata PalAsiatica. 57 (2): 117–132. doi:10.19615/j.cnki.1000-3118.190115.
  84. Nabavizadeh, A. (2019). "Cranial musculature in herbivorous dinosaurs: a survey of reconstructed anatomical diversity and feeding mechanisms". The Anatomical Record. 303 (4): 1104–1145. doi: 10.1002/ar.24283 . PMID   31675182. S2CID   207815224.
  85. Button, D. J.; Zanno, L. E. (2019). "Repeated evolution of divergent modes of herbivory in non-avian dinosaurs". Current Biology. 30 (1): 158−168.e4. doi: 10.1016/j.cub.2019.10.050 . PMID   31813611. S2CID   208652510.
  86. Tanaka, K.; Kobayashi, Y.; Zelenitsky, D. K.; Therrien, F.; Lee, Y.-N.; Barsbold, R.; Kubota, K.; Lee, H.-J.; Tsogtbaatar, C.; Idersaikhan, D. (2019). "Exceptional preservation of a Late Cretaceous dinosaur nesting site from Mongolia reveals colonial nesting behavior in a non-avian theropod" . Geology. 47 (9): 843−847. Bibcode:2019Geo....47..843T. doi:10.1130/G46328.1. S2CID   198412503.
  87. Smith, D. K.; Sanders, R. K.; Wolfe, D. G. (2020). "Vertebral pneumaticity of the North American therizinosaur Nothronychus". Journal of Anatomy. 238 (3): 598−614. doi:10.1111/joa.13327. PMC   7855063 . PMID   33044012.
  88. Smith, D. K. (2021). "Hind limb muscle reconstruction in the incipiently opisthopubic large therizinosaur Nothronychus (Theropoda; Maniraptora)". Journal of Anatomy. 238 (6): 1404–1424. doi:10.1111/joa.13382. PMC   8128771 . PMID   33417263.
  89. Smith, D. K. (2021). "Forelimb musculature and function in the therizinosaur Nothronychus (Maniraptora, Theropoda)". Journal of Anatomy. 239 (2): 307–335. doi:10.1111/joa.13418. PMC   8273597 . PMID   33665832.
  90. Liao, C.-C.; Zanno, L. E.; Wang, S.; Xu, X. (2021). "Postcranial osteology of Beipiaosaurus inexpectus (Theropoda: Therizinosauria)". PLOS ONE. 16 (9): e0257913. Bibcode:2021PLoSO..1657913L. doi: 10.1371/journal.pone.0257913 . PMC   8483305 . PMID   34591927.
  91. Hattori, S.; Kawabe, S.; Imai, T.; Shibata, M.; Miyata, K.; Xu, X.; Azuma, Y. (2021). "Osteology of Fukuivenator paradoxus: a bizarre maniraptoran theropod from the Early Cretaceous of Fukui, Japan" (PDF). Memoir of the Fukui Prefectural Dinosaur Museum. 20: 1–82.
  92. Kundrát, M.; Cruickshank, A. R. (2023). "New information on multispherulitic dinosaur eggs: Faveoloolithidae and Dendroolithidae". Historical Biology. 34 (6): 1072−1084. doi:10.1080/08912963.2021.1961764. S2CID   238687752.
  93. Sennikov, A. G. (2021). "The Plantigrade Segnosaurians: Sloth Dinosaurs or Bear Dinosaurs?". Paleontological Journal. 55 (7): 1158–1185. doi:10.1134/S0031030121100087. S2CID   245539994.
  94. Kobayashi, Y.; Takasaki, R.; Fiorillo, A. R.; Chinzorig, T.; Hikida, Y. (2022). "New therizinosaurid dinosaur from the marine Osoushinai Formation (Upper Cretaceous, Japan) provides insight for function and evolution of therizinosaur claws". Scientific Reports. 12 (7207): 7207. Bibcode:2022NatSR..12.7207K. doi: 10.1038/s41598-022-11063-5 . PMC   9065154 . PMID   35504901.
  95. Qin, Z.; Liao, C.-C.; Benton, M. J.; Rayfield, E. J. (2023). "Functional space analyses reveal the function and evolution of the most bizarre theropod manual unguals". Communications Biology. 6 (181): e12640. doi: 10.1038/s42003-023-04552-4 . PMC   9935540 . PMID   36797463.
  96. Smith, D. K.; Gillette, D. D. (2023). "Reconstruction of soft noncontractile tissue in the derived therizinosaur Nothronychus: The interplay of soft tissue and stress on hindlimb ossification and posture". Journal of Morphology. 284 (5): e21579. doi:10.1002/jmor.21579. PMID   36929022. S2CID   257583565.
  97. Smith, D. K. (2023). "Hindlimb Musculature of the Lower Cretaceous (Barremian) Therizinosaur Falcarius utahensis (Maniraptora, Theropoda) with Implications for Evolution, Stance, and Stride". Cretaceous Research. 149: 105557. Bibcode:2023CrRes.14905557S. doi:10.1016/j.cretres.2023.105557. S2CID   258177949.
  98. Wills, S.; Underwood, C. J.; Barrett, P. M. (2023). "Machine learning confirms new records of maniraptoran theropods in Middle Jurassic UK microvertebrate faunas". Papers in Palaeontology. 9 (2): e1487. doi: 10.1002/spp2.1487 .