Wulong bohaiensis

From WikiProjectMed
Jump to navigation Jump to search

Wulong bohaiensis
Temporal range: Early Cretaceous (Aptian) 120.3 Ma
Skeleton of the holotype
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Saurischia
Clade: Theropoda
Family: Dromaeosauridae
Clade: Microraptoria
Genus: Wulong
Poust et al., 2020
Species:
W. bohaiensis
Binomial name
Wulong bohaiensis
Poust et al., 2020

Wulong (meaning "dancing dragon") is a genus of microraptorine dromaeosaurid dinosaurs from the Early Cretaceous (Aptian) Jiufotang Formation of China. The genus includes a single species, Wulong bohaiensis. The skeletal remains, which include preserved feathers, represent a juvenile.[1][2][3]

Discovery

Diagram of the preserved plumage

The Wulong holotype specimen, DNHM D2933, was found by a farmer in layers of the fossil-rich Jiufotang Formation (Shangheshou locality) of Chaoyang, Liaoning Province, China. The fossil, housed at the Dalian Natural History Museum in Liaoning, consists of a complete, articulated specimen with preserved feathers. In 2014, Ashley William Poust analyzed the skeleton, naming it "Wulong bohaiensis" in a thesis.[4] This name remained an invalid nomen ex dissertatione.

In 2020, Poust alongside his former advisor David Varricchio from Montana State University and Dalian paleontologists Gao Chunling, Wu Jianlin, and Zhang Fengjiao validly named and described the type species Wulong bohaiensis. The generic name, "Wulong", is derived from the Chinese 舞, , meaning "dancing", in reference to the specimen's "sprightly pose and inferred nimble habits", and 龍/龙, lóng, meaning "dragon". The specific name, "bohaiensis", refers to the museum housing the specimen, located near the Bohai Strait (渤海, Bó Hǎi).[1]

Description

The proportionally long tail of Wulong is about twice as long as its body. The skeleton has hollow bones. The remains belong to a juvenile individual, about one-year-old.[1][5]

The long, narrow skull of Wulong is large in relation to the body. It is 1.15 times the length of the femur. Its thin jaws are filled with small and sharp teeth. The lightly-built premaxilla—a pair of small bones at the end of the upper jaw—is relatively dorsoventrally short for a dromaeosaurid. The quadratojugal of most dromaeosaurids is T-shaped, but in Wulong this bone is tiny and L‐shaped. The ascending process is about 6 mm tall, and the jugal process is 5 mm long.[1]

Feathers and colouration

Life restoration with colouration inferred from the holotype

The specimen displays soft tissue preservation, including feathered wings on its arms and legs, and two long plumes at the end of the tail, similar to the extinct Microraptor and Confuciusornis and the extant quetzal. However unlike the related Microraptor, there is no evidence that Wulong had a fan of feathers at the end of the tail. The long pair tail feathers present in an immature individual suggests that they were likely not used for mating, and possibly not other ornamental purposes.[1]

In 2023, Croudace and colleagues described the likely plumage colouration of the holotype. They indicated the presence of iridescent feathers on the forelimbs and hindlimbs, with grey feathers on the rest of the body. They further hypothesized that iridescence in juvenile paravians may not only indicate sexual signalling, but also intraspecific signalling for communication.[5]

Classification

Poust et al. (2020) recovered Wulong as a microraptorine member of the Dromaeosauridae, as the sister taxon to the slightly older Sinornithosaurus from the Yixian Formation. The results of their phylogenetic analyses are shown in the cladogram below:[1]

Microraptorinae

See also

References

  1. ^ a b c d e f Poust, AW; Gao, C; Varricchio, DJ; Wu, J; Zhang, F (15 January 2020). "A new microraptorine theropod from the Jehol Biota and growth in early dromaeosaurids". The Anatomical Record. American Association for Anatomy. doi:10.1002/ar.24343. PMID 31943887.
  2. ^ Hodge, Rae (17 January 2020). "Pocket-size raptor sheds new light on the links between dino and bird life - This "dancing dragon," a new species of feathered dinosaur, was discovered in one of the richest fossil deposits in the world". CNET. Retrieved 19 January 2020.
  3. ^ Rayne, Elizabeth (18 January 2020). "This New Dinosaur Just Called It: Even Feathered Dinos Were Nothing Like Birds". SyfyWire. Retrieved 19 January 2020.
  4. ^ Poust, Ashley W. (2014). Description and ontogenetic assessment of a new Jehol microraptorine (PDF) (MSc). Montana State University.
  5. ^ a b Croudace, A.D.; Shen, C.; Lü, J.; Brusatte, S.L.; Vinther, J. (2023). "Iridescent plumage in a juvenile dromaeosaurid theropod dinosaur". Acta Palaeontologica Polonica. 68. doi:10.4202/app.01004.2022. hdl:20.500.11820/6f4df584-274a-45d9-a09b-487425ff9569.