Jian
From Chinese 'jiān' (鹣), a mythical one-winged bird; alluding to the bird-like, probably volant nature of this microraptorine.
Early Cretaceous stages
Jian changmaensis is an extinct species of microraptorine theropod dinosaur known from the Early Cretaceous (Aptian age) Xiagou Formation of China. J. changmaensis is the only species in the genus Jian, known from a pectoral girdle and partial forelimb. After the discovery of more than 100 bird fossils in the formation, this specimen is the first non-avian dinosaur to be described from it.
Diagnosis
- Coracoid proportionally longer relative to humerus than in any other microraptorine (~36% of humerus length).
- Humeral distal condyles developed primarily on the cranial surface of the bone rather than the craniodistal surface.
- Well-developed foramen on the ventral (proximoventral) aspect of the proximal radius, not described in other dromaeosaurids.
Species
Jian changmaensis Zhou et al., 2026
Type species
From Changma (昌马), the locality in the Changma Basin of Gansu Province, China, where the holotype was found.
- Holotype
- GSGM-D050 , Gansu Geological Museum
- Material
- Articulated partial left pectoral girdle and forelimb: complete scapulocoracoid, humerus, radius, and ulna; carpus and manus absent.
- Horizon
- Xiagou Formation, Aptian, Early Cretaceous , 121.4–113.2 million years ago
- Locality
- Changma, Gansu, China
References
- Zhou, L. Q.; Lamanna, M. C.; Poust, A. W.; Li, D. Q.; You, H. L.; O'Connor, J. K. (2026). First non-avian theropod (Dromaeosauridae, Microraptorinae) from the bird-bearing Lower Cretaceous Xiagou Formation of the Changma Basin, Gansu Province, northwestern China. Annals of Carnegie Museum 92(2): 89-110. zhou2026a