Sinocalliopteryx
From Latin 'Sinae' (China) + Greek 'kalos' (beautiful) + Greek 'pteryx' (feather, wing), meaning 'Chinese beautiful feather'.
Sinocalliopteryx is a genus of carnivorous coelurosaurian theropod dinosaurs from the Lower Cretaceous Yixian Formation of China (Jianshangou Beds, dating to 124.6 Ma). While similar to the related Huaxiagnathus, Sinocalliopteryx were larger. In 2007, the type specimen was the largest known compsognathid exemplar, at 2.37 meters (7.8 ft) in length. In 2012, an even larger specimen was reported.
Under dispute
Sinocalliopteryx was described as a basal compsognathid, a placement followed by many authors and by Jones (2026). Hartman and colleagues (2019) instead recovered it as a basal maniraptoromorph outside a reduced Compsognathidae, and Qiu and colleagues (2025) placed it with the other Jehol taxa in Sinosauropterygidae. It is retained in Compsognathidae in the family's traditional sense; those alternatives are reflected in the Compsognathidae clade dispute.
Diagnosis
- Very large compsognathid (2.37 m long) with 49 caudal vertebrae
- Manus as long as humerus plus radius, with very large and subequally long manual unguals I and II
- Smaller proximal transverse width of the first metacarpal and reduced olecranon process on the ulna
- Long maxillary process of premaxilla not extending to the vertical level of the maxillary antorbital fossa
- Proportionally longer ulna than Huaxiagnathus (humerus:ulna ratio 114% vs. 160%); preacetabular wing of ilium bending downward at anteroventral margin; distally unfused ischia
Species
Sinocalliopteryx gigas Ji et al., 2007
Type species
From Greek 'gigas' meaning 'giant', referring to the unusually large size of this dinosaur compared to its compsognathid relatives.
- Holotype
- JMP-V-05-8-01 , Jinzhou Museum of Paleontology
- Material
- Nearly complete skeleton with skull, protofeathers preserved
- Horizon
- Jianshangou Member, Yixian Formation, Barremian, Early Cretaceous , 125.8–121.4 million years ago
- Locality
- Hengdaozi, Sihetun, Liaoning, China
Notable specimens
-
CAGS-IG-T1
Institute of Geology, Chinese Academy of Geological Sciences gut contents
Referred specimen larger than the holotype, preserving remains of several meals: disarticulated bones of at least two Confuciusornis sanctus and a 13.5 cm ornithischian scapula etched by stomach acid, suggesting a high metabolism and a possible specialization on bird prey.
References
- Xing, L.; Bell, P. R.; Persons, W. S., IV; Ji, S.; Miyashita, T.; Burns, M. E.; Ji, Q.; Currie, P. J. (2012). Abdominal contents from two large Early Cretaceous compsognathids (Dinosauria: Theropoda) demonstrate feeding on confuciusornithids and dromaeosaurids. PLoS ONE 7(8): e44012. Public Library of Science (PLoS). doi:10.1371/journal.pone.0044012 xing2012a
- Ji, S.; Ji, Q.; Lü, J.; Yuan, C. (2007). A new giant compsognathid dinosaur with long filamentous integuments from Lower Cretaceous of northeastern China. Acta Geologica Sinica (English Edition) 81(1): 8-15. ji2007a
-
Paul, G. S. (2024). The Princeton Field Guide to Dinosaurs (3rd ed.). Princeton University Press.
Source of the mass estimate.
paul2024a -
Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Theropods. Princeton University Press.
Source of the hip height estimate, and the appearance features.
jones2026c -
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. PeerJ. doi:10.7717/peerj.7247
Recovered Sinocalliopteryx as a basal maniraptoromorph outside a reduced Compsognathidae.
hartman2019a -
Qiu, R.; Wang, X.; Jiang, S.; Meng, J.; Zhou, Z. (2025). Two new compsognathid-like theropods show diversified predation strategies in theropod dinosaurs. National Science Review 12(5). Oxford University Press (OUP). doi:10.1093/nsr/nwaf068
Placed Sinocalliopteryx with other Jehol taxa in Sinosauropterygidae.
qiu2025a