FIGURE 1. Comparison of the fossil Tadorna sp. (IVPP V20114) in 1 and 2 , and the coracoid of Tadorna ferruginea (IVPP OV1745) in 3 and 4. 1 and 3 are in dorsal view, and 2 and 4 are in ventral view. Abbreviations: g-glenoid; mr-muscular ridges; p-procoracoid process; pn-procoracoid notch; sa-sternal articulation; sc-scapular cotyle; and vs-ventral sternal articulation.
FIGURE 2. 1 map of Qaidam Basin showing major areas of vertebrate fossil-producing localities (modified from Wang et al., 2007, figure 1). 2 satellite image of the Yanhu Anticline showing the location of the fossil bird locality (CD0514) and other fossil mammal localities. 3 stratigraphic occurrences of vertebrate and ostracod fossils. Yanhu surface and drill sections, as well as ostracod occurrences, are based on unpublished data of Sun Zhencheng, archived in the China University of Petroleum.
FIGURE 3. Photograph of the Yanhu Anticline exposures. The wind-eroded exposures are mostly oriented along the prevailing winter northwesterly winds, roughly coinciding with the axis of the anticline. Person in foreground for scale (photo by Xiaoming Wang).