Yi qi

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Time: Middle–Late Jurassic (~160 million years ago)

Region: Hebei Province, China

Formation: Tiaojishan Formation

Coloration Data

Yi qi was first described by Xu et al. (2015) based on specimen STM 31-2. To investigate feather melanosomes, samples were gathered from the head, neck, shoulder, elbow, and lower leg. The analysis revealed that different parts of the body possessed distinct melanosome assemblages. Consequently, Yi qi likely displayed a variegated color pattern: predominantly dark hues (grey, black, and brown) in its plumage, potentially with reddish patches on the head, while the membranous wings may have been lighter. A total of 12 samples across the body were analyzed, including feathers above the cranium, on the neck, along the humerus, along the ulna, and along the tibia, as well as membranous soft tissue adjacent to digit II and digit IV.

Method: Scanning electron microscopy (SEM).

Publications

• Xing Xu, Xiaoting Zheng, Corwin Sullivan, Xiaoli Wang, Lida Xing, Yan Wang, Xiaomei Zhang, Jingmai K. O’Connor, Fucheng Zhang & Yanhong Pan (2015)
  An article describing Yi qi and its coloration.
• Arindam Roy, Michael Pittman, Evan T. Saitta, Thomas G. Kaye, Xing Xu (2020)
  An overview article on the paleo‑coloration of amniotes.

Documents and files

• Xu_et_al_2015.pdf (PDF)
  Article from Nature describing Yi qi.
• Roy_et_al_2020.pdf (PDF)
  Review article on amniote paleocolor in Biological Reviews of the Cambridge Philosophical Society.

Reconstructions

Fossils

Size comparison