Giant Dromaeosaurs and other Eumaniraptora from the Cretaceous period

[Joseph Fossil]

The Eumaniraptora is a clade of non-avian theropod dinosaurs that first emerged during the late Jurassic period and diversified extensively during the subsequent Cretaceous period (143-66 Million years ago). This group is most famously known as the Raptor dinosaurs (the sister clade of the theropod dinosaurs that gave direct rise to the birds), consisting of mostly small to mid sized theropod dinosaurs. There are a few species though that exceed the typical small-medium size range for the raptor dinosaurs. Only a few giant raptor dinosaurs are currently known. But recent discoveries over the past few decades have demonstrated large raptor dinosaurs were less of an exception in Cretaceous ecosystems than previously thought. Here is a list of all the currently known giant Eumaniraptora from the fossil record which hopefully can expand our understanding the vital roles these animals played in the ecosystems they once inhabited. Let me know if I forgot any examples.

 

 

South America

 

Austroraptor cabazai (Dromaeosauridae - Argentina, South America) (Late Cretaceous (78-66 Million Years ago))

(grew up to 6 meters (20 feet) in length)

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2679073/

 

 

 

Antarctica

 

Imperobator antarcticus (Eumaniraptora - part of what is now James Ross Island, Antarctica) (Late Cretaceous (71 Million Years ago))

(grew up to 4 meters (13 feet) in length, note: did not have the iconic pair of sickle shaped claw on its feet like most other Eumaniraptora)

https://www.sciencedirect.com/science/article/abs/pii/S0195667118300120?via%3Dihub

 

 

Asia

 

Achillobator giganticus (Dromaeosauridae - part of what is now Mongolia, Asia) (Late Cretaceous (96-89 Million Years ago))

(grew up to 5 meters (16 feet) in length)

Perle, A.; Norell, M. A.; Clark, J. M. (1999). "A new maniraptoran Theropod−Achillobator giganticus (Dromaeosauridae)−from the Upper Cretaceous of Burkhant, Mongolia". Contributions from the Geology and Mineralogy Chair, National Museum of Mongolia (101): 1−105.

 

Unnamed Bissekty Formation Giant Dromaeosauridae (Dromaeosauridae (could possible be a species of Itemirus) - part of what is now Uzbekistan, Asia) (Late Cretaceous (92-90 Million Years ago))

(based on Specimens CCMGE 600/12457, ZIN PH 11/16, grew up to 5.5 meters (18 feet) in length)

https://www.researchgate.net/publication/263891965_Dromaeosauridae_Dinosauria_Theropoda_from_the_Bissekty_Formation_Upper_Cretaceous_Turonian_of_Uzbekistan_and_the_phylogenetic_position_of_Itemirus_medullaris_Kurzanov_1976

 

https://www.cambridge.org/core/journals/geological-magazine/article/abs/giant-dromaeosaurid-theropod-from-the-upper-cretaceous-turonian-bissekty-formation-of-uzbekistan-and-the-status-of-ulughbegsaurus-uzbekistanensis/4543ABAB1EC19C84405EDF66A5F53124

 

 

Europe

 

Unnamed Wessex Formation Giant Dromaeosauridae (Dromaeosauridae (specimens for this species could belong to Vectiraptor) - Isle of Wight, Great Britain, Europe) (Early Cretaceous (125 Million Years ago))

(based on Specimens IWCMS.2002.1, IWCMS.2002.3, IWCMS.2002.4., and BMNH R 16510, grew up to 5.5 meters (18 feet) in length)

https://www.researchgate.net/publication/222830089_The_first_record_of_velociraptorine_dinosaurs_Saurischia_Theropoda_from_the_Wealden_Early_Cretaceous_Barremian_of_southern_England

 

https://www.sciencedirect.com/science/article/abs/pii/S0195667121003712

 

 

Unnamed Giant Dromaeosauridae (Dromaeosauridae - Gorodishchenskii District Russia, Europe) (Late Cretaceous (72.1-66.0 Million Years ago))

(based on Specimen VGI. no. 231/2, grew up to 5.8 meters (19 feet) in length)

https://www.researchgate.net/publication/235806763_Carnivorous_dinosaurs_Saurischia_Theropoda_from_the_Maastrichtian_of_the_Volga-Don_Interfluve_Russia

 

 

North America

 

Utahraptor ostrommaysi (Dromaeosauridae - Western North America) (Early Cretaceous (135-130 Million Years ago))

(grew up to 5.5 meters (18 feet) in length)

https://www.researchgate.net/publication/285714464_A_large_dromaeosaur_Theropoda_from_the_Lower_Cretaceous_of_eastern_Utah

 

Dakotaraptor steini (Dromaeosauridae - Western North America) (Late Cretaceous (66 Million years ago))

(grew up to 5.5 meters (18 feet) in length)

https://www.researchgate.net/publication/283655219_The_first_giant_raptor_Theropoda_Dromaeosauridae_from_the_Hell_Creek_Formation

 

Unnamed Marshalltown Formation Giant Dromaeosauridae (Dromaeosauridae - Eastern North America) (Late Cretaceous (72.1 Million Years ago))

(based on Specimen NJSM 14158, grew up to 5.5 meters (18 feet) in length)

https://www.researchgate.net/publication/327117985_The_distinctive_theropod_assemblage_of_the_Ellisdale_site_of_New_Jersey_and_its_implications_for_North_American_dinosaur_ecology_and_evolution_during_the_Cretaceous

 

https://terpconnect.umd.edu/~gdouglas/raptor/index.html

 

 

Unnamed Tar Heel Formation Giant Dromaeosauridae ((Dromaeosauridae - Eastern North America) (Late Cretaceous (78.5-77.1 Million Years ago))

(Based on Specimen YPM.VPPU.021397, grew up to 3.4 meters (11 feet 2 inches) in length)

https://peerj.com/preprints/26829/

 

Alaska Troodontid (Troodontidae (could be a species of Troodon or a new genus in Troodontidae) - Prince Creek Formation Alaska, Western North America) (Late Cretaceous (70.6-69.1 Million Years ago)

(grew up to almost 4 meters (13 feet) in length)

https://www.researchgate.net/publication/236632883_On_the_Occurrence_of_Exceptionally_Large_Teeth_of_Troodon_Dinosauria_Saurischia_from_the_Late_Cretaceous_of_Northern_Alaska

 

Latenivenatrix mcmasterae (Troodontidae - Dinosaur Park Formation, Alberta Canada, Western North America) (Late Cretaceous (75.5 Million years ago))

(grew up to 3.5 meters (11.5 feet) in length)

https://tspace.library.utoronto.ca/bitstream/1807/78296/1/cjes-2017-0031.pdf

 

Unnamed Mount Laurel Formation Giant Dromaeosauridae (Dromaeosauridae - Eastern North America) (Late Cretaceous (72.1 Million Years ago))

(based on Specimen NJSM GP 22949, grew up to 3.4 meters (11 feet 2 inches) in length)

https://royalsocietypublishing.org/doi/10.1098/rsos.191206

 

 

 

What do you guys think?

[Maniraptora]

Very useful reference. I was happy to see the Marshalltown Formation specimen in the list! Someone needs to find more material from that species right about... now.

[Joseph Fossil]

Also here are some more additions to this list of all currently known Giant Dromaeosaurs and other Eumaniraptora from the Cretaceous period:

 

 

Asia

 

Unnamed Troodontid (Troodontidae (could be a species of Troodon or a new genus in Troodontidae) - Kakanaut Formation, part of what is now eastern Russia, Asia) (Late Cretaceous (72.0-66.0 Million Years ago))

(Based on Specimen ZIN PH 1/28, grew up to 4.4 meters (14 feet) in length)

 

Averianov, A. O., & Sues, H.-D. (2007). A New Troodontid (Dinosauria: Theropoda) from the Cenomanian of Uzbekistan, with a Review of Troodontid Records from the Territories of the Former Soviet Union. Journal of Vertebrate Paleontology, 27(1), 87–98. http://www.jstor.org/stable/4524669

 https://www.jstor.org/stable/4524669?seq=8

 

 

Unnamed Tianjialou Formation Giant Deinychsaurid (Dromeaosauridae (called tentatively Dromaeopodus shandongensis) - Tianjialou Formation Northern China, Asia) (Early Cretaceous (129.4-113.0 Million Years ago))

(grew up to 5 meters (16 feet) in length)

 

Li, R., Lockley, M.G., Makovicky, P.J., Matsukawa, M., Norell, M.A., Harris, J.D., & Liu, M. (2008). Behavioral and faunal implications of Early Cretaceous deinonychosaur trackways from China. Naturwissenschaften, 95, 185-191.

https://cactus.utahtech.edu/jharris/Dromaeopodus.pdf

 

 

North America

 

Unnamed Saurornitholestes sp. (Dromaeosauridae (could be a large individual of the species Saurornitholestes langstoni or a new species of Saurornitholestes) – Texas US, Western North America) (Late Cretaceous (81.5-76.9 Million Years ago))

(Based on Specimens LSUMG 140:6139, LSUMG 140:6140, LSUMG 140:6183, LSUMG 140:6185, LSUMG 489:5659, LSUMG 491:5950, and LSUMG 492:5158, grew up to 3.5 meters (11 feet 5 inches) in length)

 

Rowe, T., Cifelli, R.L., Lehman, T.M. and Weil, A., (1992). The Campanian Terlingua

local fauna, with a summary of other vertebrates from the Aguja Formation,

Trans-Pecos Texas: Journal of Vertebrate Paleontology, v. 12, p. 472-493.

https://www.jsg.utexas.edu/rowe/files/017-Rowe-et-al-19921.pdf

 

Sankey, J. T. (2001). Late Campanian Southern Dinosaurs, Aguja Formation, Big Bend, Texas. Journal of Paleontology, 75(1), 208–215. http://www.jstor.org/stable/1306931

https://www.jstor.org/stable/1306931?seq=7

 

 

Mexico Troodontid (Troodontidae (could be a species of Troodon or a new genus in Troodontidae) – Mexico, North America) (Late Cretaceous (72.0-66.0 Million Years ago))

(Based on Unnamed footprint Specimen Morfotipo C, grew up to 5 meters (16 feet) in length)

 

Ortiz-Mendieta (2001). Dinosauricnitas Cretácico-tardías de El Aguaje, Michoacán, región 

suroccidental de México y sus implicaciones geológico-paleontológicas, Tesis de Licenciatura, México: Universidad Nacional Autónoma de México, Facultad de Ciencias, 2001. 

 

Mazzei, S., Connolly, D., Ramírez Cruz, G., Larramendi, A. & Atuchin, A. (2019). Comparing species. In Dinosaur Facts and Figures: The Theropods and Other Dinosauriformes (pp. 60-61). Princeton: Princeton University Press. https://doi.org/10.1515/9780691190594-006

 

 

Unnamed Lewisville Formation Giant Dromaeosaurid (Dromaeosauridae - Woodbine Group Lewisville Formation, Texas US, North America) (Late Cretaceous (100-95 Million Years ago))

(Based on Specimens DMNH 2014-06-02 and DMNH 2013-07-1080, grew up to 5 meters (16 feet) in length)

 

Noto, Christopher & D'Amore, Domenic & Drumheller, Stephanie & Adams, Thomas. (2022). A newly recognized theropod assemblage from the Lewisville Formation (Woodbine Group; Cenomanian) and its implications for understanding Late Cretaceous Appalachian terrestrial ecosystems. PeerJ. 10. e12782. 10.7717/peerj.12782.

https://www.researchgate.net/publication/358106122_A_newly_recognized_theropod_assemblage_from_the_Lewisville_Formation_Woodbine_Group_Cenomanian_and_its_implications_for_understanding_Late_Cretaceous_Appalachian_terrestrial_ecosystems

 

 

 

[Joseph Fossil]

Also here is a update on the size of the Unnamed Bissekty Formation Giant Dromaeosauridae, a numbered smaller list of which of these Eumaniraptora were the largest, and a list showing the Cretaceous geologic age of these Giant Eumaniraptoras from youngest to oldest.

 

Unnamed Bissekty Formation Giant Dromaeosauridae (Dromaeosauridae (could possible be a species of Itemirus) - part of what is now Uzbekistan, Asia) (Late Cretaceous (92-90 Million Years ago))

(based on Specimens CCMGE 600/12457, ZIN PH 11/16, grew up to 7 meters (22 feet 9 inches) in length)

https://www.researchgate.net/publication/263891965_Dromaeosauridae_Dinosauria_Theropoda_from_the_Bissekty_Formation_Upper_Cretaceous_Turonian_of_Uzbekistan_and_the_phylogenetic_position_of_Itemirus_medullaris_Kurzanov_1976

 

https://www.cambridge.org/core/journals/geological-magazine/article/abs/giant-dromaeosaurid-theropod-from-the-upper-cretaceous-turonian-bissekty-formation-of-uzbekistan-and-the-status-of-ulughbegsaurus-uzbekistanensis/4543ABAB1EC19C84405EDF66A5F53124

 

 

 

 

The Largest to smallest of the Currently known Giant Eumaniraptora taxon of the Cretaceous

 

1. Unnamed Bissekty Formation Giant Dromaeosauridae (Dromaeosauridae)

(based on Specimens CCMGE 600/12457, ZIN PH 11/16, grew up to 7 meters (22 feet 9 inches) in length)

 

2. Austroraptor cabazai (Dromaeosauridae)

(grew up to 6 meters (20 feet) in length)

 

3. Unnamed Gorodishchenskii District Giant Dromaeosauridae (Dromaeosauridae)

(based on Specimen VGI. no. 231/2, grew up to 5.8 meters (19 feet) in length)

 

4. Utahraptor ostrommaysi (Dromaeosauridae)

(grew up to 5.5 meters (18 feet) in length)

 

5. Dakotaraptor steini (Dromaeosauridae)

(grew up to 5.5 meters (18 feet) in length)

 

6. Unnamed Wessex Formation Giant Dromaeosauridae (Dromaeosauridae)

(based on Specimens IWCMS.2002.1, IWCMS.2002.3, IWCMS.2002.4., and BMNH R 16510, grew up to 5.5 meters (18 feet) in length)

 

7. Unnamed Marshalltown Formation Giant Dromaeosauridae (Dromaeosauridae)

(based on Specimen NJSM 14158, grew up to 5.5 meters (18 feet) in length)

 

8. Unnamed Tianjialou Formation Giant Deinychsaurid (Dromeaosauridae)

(grew up to 5 meters (16 feet) in length)

 

9. Unnamed Lewisville Formation Giant Dromaeosaurid (Dromaeosauridae)

(Based on Specimens DMNH 2014-06-02 and DMNH 2013-07-1080, grew up to 5 meters (16 feet) in length)

 

10. Unnamed Mexico Troodontid (Troodontidae)

(Based on Unnamed footprint Specimen Morfotipo C, grew up to 5 meters (16 feet) in length)

 

11. Achillobator giganticus (Dromaeosauridae - part of what is now Mongolia, Asia) (Late Cretaceous (96-89 Million Years ago))

(grew up to 5 meters (16 feet) in length)

 

12. Unnamed Kakanaut Formation Troodontid (Troodontidae)

(Based on Specimen ZIN PH 1/28, grew up to 4.4 meters (14 feet) in length)

 

13. Imperobator antarcticus (Eumaniraptora)

(grew up to 4 meters (13 feet) in length, note: did not have the iconic pair of sickle shaped claw on its feet like most other Eumaniraptora)

 

14. Alaska Troodontid (Troodontidae)

(grew up to almost 4 meters (13 feet) in length)

 

15. Unnamed Saurornitholestes sp. (Dromaeosauridae)

(Based on Specimens LSUMG 140:6139, LSUMG 140:6140, LSUMG 140:6183, LSUMG 140:6185, LSUMG 489:5659, LSUMG 491:5950, and LSUMG 492:5158, grew up to 3.5 meters (11 feet 5 inches) in length)

 

16. Latenivenatrix mcmasterae (Troodontidae)

(grew up to 3.5 meters (11.5 feet) in length)

 

17. Unnamed Tar Heel Formation Giant Dromaeosauridae (Dromaeosauridae)

(Based on Specimen YPM.VPPU.021397, grew up to 3.4 meters (11 feet 2 inches) in length)

 

18. Unnamed Mount Laurel Formation Giant Dromaeosauridae (Dromaeosauridae)

(based on Specimen NJSM GP 22949, grew up to 3.4 meters (11 feet 2 inches) in length)

 

 

 

 

 

The Geologically Youngest to Oldest of the Currently known Giant Eumaniraptora taxon of the Cretaceous

 

1. Dakotaraptor steini (Dromaeosauridae - Western North America) (Late Cretaceous (66 Million years ago))

 

2. Alaska Troodontid (Troodontidae) - Prince Creek Formation Alaska, Western North America) (Late Cretaceous (70.6-69.1 Million Years ago)

 

3. Imperobator antarcticus (Eumaniraptora - part of what is now James Ross Island, Antarctica) (Late Cretaceous (71 Million Years ago))

 

4. Unnamed Troodontid (Troodontidae (could be a species of Troodon or a new genus in Troodontidae) - Kakanaut Formation, part of what is now eastern Russia, Asia) (Late Cretaceous (72.0-66.0 Million Years ago))

 

5. Unnamed Mexico Troodontid (Troodontidae (could be a species of Troodon or a new genus in Troodontidae) – Mexico, North America) (Late Cretaceous (72.0-66.0 Million Years ago))

 

6. Unnamed Giant Dromaeosauridae (Dromaeosauridae - Gorodishchenskii District Russia, Europe) (Late Cretaceous (72.1-66.0 Million Years ago))

 

7. Unnamed Marshalltown Formation Giant Dromaeosauridae (Dromaeosauridae - Eastern North America) (Late Cretaceous (72.1-66.0 Million Years ago))

 

8. Unnamed Mount Laurel Formation Giant Dromaeosauridae (Dromaeosauridae - Eastern North America) (Late Cretaceous (72.1-66.0 Million Years ago))

 

9. Latenivenatrix mcmasterae (Troodontidae - Dinosaur Park Formation, Alberta Canada, Western North America) (Late Cretaceous (75.5 Million years ago))

 

10. Austroraptor cabazai (Dromaeosauridae - Argentina, South America) (Late Cretaceous (78-66 Million Years ago))

 

11. Unnamed Tar Heel Formation Giant Dromaeosauridae ((Dromaeosauridae - Eastern North America) (Late Cretaceous (78.5-77.1 Million Years ago))

 

12. Unnamed Saurornitholestes sp. (Dromaeosauridae (could be a large individual of the species Saurornitholestes langstoni or a new species of Saurornitholestes) – Texas US, Western North America) (Late Cretaceous (81.5-76.9 Million Years ago))

 

13. Achillobator giganticus (Dromaeosauridae - part of what is now Mongolia, Asia) (Late Cretaceous (96-89 Million Years ago))

 

14. Unnamed Bissekty Formation Giant Dromaeosauridae (Dromaeosauridae (could possible be a species of Itemirus) - part of what is now Uzbekistan, Asia) (Late Cretaceous (92-90 Million Years ago))

 

15. Unnamed Lewisville Formation Giant Dromaeosaurid (Dromaeosauridae - Woodbine Group Lewisville Formation, Texas US, North America) (Late Cretaceous (100-95 Million Years ago))

 

16. Unnamed Wessex Formation Giant Dromaeosauridae (Dromaeosauridae (specimens for this species could belong to Vectiraptor) - Isle of Wight, Great Britain, Europe) (Early Cretaceous (125 Million Years ago))

 

17. Unnamed Tianjialou Formation Giant Deinychsaurid (Dromeaosauridae (called tentatively Dromaeopodus shandongensis) - Tianjialou Formation Northern China, Asia) (Early Cretaceous (129.4-113.0 Million Years ago))

 

18. Utahraptor ostrommaysi (Dromaeosauridae - Western North America) (Early Cretaceous (135-130 Million Years ago))

 

 

What do you think?

[NickG]

There is good reason to be skeptical of the validity overall of Dakotaraptor. 

 

First, see Arbour et al. (2016) in PeerJ:

https://doi.org/10.7717/peerj.1691

 

Then Jasinski et al. (2020) in Scientific Reports:

 

Quote

Soon after, a second dromaeosaurid, Dakotaraptor steini, was named by DePalma et al.¹⁴ from the Hell Creek Formation of South Dakota based on material from a larger individual and represented by portions of the fore- and hindlimbs and axial skeleton. It is noted that Dakotaraptor is likely a chimera and portions of the described skeleton have already been shown to not represent a dromaeosaurid, namely with the “furcula” reidentified as part of a turtle plastron.

 

In the past and recently theropod expert, Dr. Andrea Cau, has espoused a great deal of uncertainty whether any of the material can be referred to a dromaeosaurid. Now, obviously, a blog post is NOT peer-reviewed and should also be taken with a grain of salt, but Dr. Cau raises several good points why we might be doubtful about Dakotaraptor's authenticity.

 

See: https://theropoda.blogspot.com/2015/10/dakotaraptor-un-acheroraptor-gigante.html & https://theropoda.blogspot.com/2015/12/oh-mio-dio-dakotaraptor-non-esiste.html & https://theropoda.blogspot.com/2023/09/dakotaraptor-non-esiste.html & https://theropoda.blogspot.com/2023/09/le-vere-dimensioni-di-dakotaraptor.html

 

I'm not saying it's completely invalid, but I do think the issue of uncertainty around the material should be considered when listing it as a giant dromaeosaur.

Edited October 23, 2023 by Nick G.
Added two more links

[Joseph Fossil]

5 hours ago, Nick G. said:

There is good reason to be skeptical of the validity overall of Dakotaraptor. 

 

First, see Arbour et al. (2016) in PeerJ:

https://doi.org/10.7717/peerj.1691

 

Then Jasinski et al. (2020) in Scientific Reports:

 

 

In the past and recently theropod expert, Dr. Andrea Cau, has espoused a great deal of uncertainty whether any of the material can be referred to a dromaeosaurid. Now, obviously, a blog post is NOT peer-reviewed and should also be taken with a grain of salt, but Dr. Cau raises several good points why we might be doubtful about Dakotaraptor's authenticity.

 

See: https://theropoda.blogspot.com/2015/10/dakotaraptor-un-acheroraptor-gigante.html & https://theropoda.blogspot.com/2015/12/oh-mio-dio-dakotaraptor-non-esiste.html & https://theropoda.blogspot.com/2023/09/dakotaraptor-non-esiste.html & https://theropoda.blogspot.com/2023/09/le-vere-dimensioni-di-dakotaraptor.html

 

I'm not saying it's completely invalid, but I do think the issue of uncertainty around the material should be considered when listing it as a giant dromaeosaur.

 

@Nick G. Thanks for letting me know. I've heard only occasional rumors until now that not all the fossils bones described to Dakotaraptor actually belong to a dromeosaurid (I even heard a while ago part of it actually belonged to a prehistoric turtle).  

[Joseph Fossil]

@Nick G. @Troodon Hope you like the list and do you know of any other large Eumaniraptora taxon I could add? Should I add Adasaurus too ( I heard some reports recently it could grow up to 3.5 meters (11.5 feet) in length)?

[Fossildude19]

4 minutes ago, Joseph Fossil said:

@Nick G. @Troodon

 

@Joseph Fossil

FYI, Troodon is no longer on the Forum.

[Joseph Fossil]

2 hours ago, Fossildude19 said:

 

@Joseph Fossil

FYI, Troodon is no longer on the Forum.

 

@Fossildude19 Thanks for letting me know.

[NickG]

 

10 hours ago, Joseph Fossil said:

 

@Nick G. Thanks for letting me know. I've heard only occasional rumors until now that not all the fossils bones described to Dakotaraptor actually belong to a dromeosaurid (I even heard a while ago part of it actually belonged to a prehistoric turtle).  

 

Correct - see Arbour et al. (2016) which I linked above.

[Joseph Fossil]

7 hours ago, Nick G. said:

 

 

Correct - see Arbour et al. (2016) which I linked above.

@Nick G. Thanks for the article link!!! Also, what about adding Adasaurus here?

 

[Joseph Fossil]

Another Giant and Unnamed genus of Dromaeosaur was discovered and described in China's Late Cretaceous Quantou Formation. 

 

https://www.sciencedirect.com/science/article/abs/pii/S0195667123002392