Figure 1.
Geographic location of the Changma Basin (indicated by star), Gansu Province, People’s Republic of China.
Figure 2.
Photograph of Yumenornis huangi gen. et sp. nov., GSGM-06-CM-013 (A) and line drawing (B).
Abbreviations: a, acromion; amc, alular metacarpal; bt, bicipital tubercle; co, coracoid; cp, craniolateral process; df, distal fossa; ff, fragment of the furcula; fit, fragment of the intermediate trabecula; hu, humerus; lp, lateral process; lt, lateral trabecula; mc II, metacarpal II; mc III, metacarpal III; md, manual digits; sc, scapula; st, sternum; str, sternal ribs; ra, radius; ul, ulna; ule, ulnare; vt, ventral tubercle.
Figure 3.
Comparison of sterna of Yumenornis huangi (C) and Jiuquanornis niui (D) with other Early Cretaceous ornithuromorphs.
A, Longicrusavis houi; B, Hongshanornis longicresta; E, Gansus yumenensis; F, Archaeorhynchus spathula; G, Yixianornis grabaui; H, Yanornis martini; I, Songlingornis linghensis. Dashed lines in C represent estimated reconstruction.
Figure 4.
Comparison of forelimbs of Yumenornis huangi (A) and other Early Cretaceous ornithuromorphs.
B, Gansus yumenensis; C, Yixianornis grabaui; D, Yanornis martini.
Figure 5.
Photograph of Changmaornis houi gen. et sp. nov., GSGM-08-CM-002 (A) and line drawing (B).
Abbreviations: cp, costal process; il, ilium; is, ischium; mec, medial epicondyle; pu, pubis; syn, synsacrum; tb, tibiotarsus; tm, tarsometatarsus; tr, thoracic rib; tv, thoracic vertebra; I- IV, pedal digit I- IV. Numbers 1-11 in B indicate the number of the sacral vertebrae.
Figure 6.
Comparison of pedes of Changmaornis houi (A) and other Early Cretaceous ornithuromorphs.
B, Schizooura lii; C, Gansus yumenensis; D, Yixianornis grabaui; E, Yanornis martini.
Figure 7.
Photograph of Jiuquanornis niu gen. et sp. nov., GSGM-05-CM-021.
Figure 8.
Strict consensus cladogram illustrating the phylogenetic positions of Yumenornis huangi, Changmaornis houi, and Jiuquanornis niui.
Tree length: 842 steps, consistency index = 0.387, retention index = 0.670.