A second Cretaceous ornithuromorph bird from the Changma Basin, Gansu Province, northwestern China

作者：You, Hai-Lu^*; Atterholt, Jessie; O'Connor, Jingmai K.; Harris, Jerald D.; Lamanna, Matthew C.; Li, Da-Qing

来源：Acta Palaeontologica Polonica, 2010, 55(4): 617-625.

DOI：10.4202/app.2009.0095

• Aves
• Ornithuromorpha
• Aptian
• Early Cretaceous
• China

Finely-bedded lacustrine deposits of the Aptian (Lower Cretaceous) Xiagou Formation exposed in the Changma Basin of Gansu Province, northwestern China, have yielded numerous fossil vertebrate remains, including approximately 100 avian specimens. Though the majority of these birds appear referable to the ornithuromorph Gansus yumenensis, a number of enantiornithine fossils have also been recovered. Here we report on a specimen consisting of a complete, three-dimensionally preserved sternum, furcula, and sternal ribs that represents a second ornithuromorph taxon from the Xiagou Formation at Changma. The fossil exhibits morphologies that distinguish it from all previously-known Xiagou birds and demonstrate that it represents a derived non-ornithurine member of Ornithuromorpha. Though it is morphologically distinct from the equivalent elements of all other described ornithuromorphs, the material is too incomplete to justify the erection of a new taxon. Nonetheless, it increases the taxonomic diversity of the Xiagou avifauna, thereby expanding our knowledge of Early Cretaceous avian diversity and evolution.

• 出版日期2010-12
• 单位甘肃地质博物馆; 中国地质科学院; 中国科学院古脊椎动物与古人类研究所