Confuciusornithids are primitive birds, which lived about 120-131 Ma years ago. All eight published confuciusornithid species belong to four genera of the family Confuciusornithidae of the order Confuciusornithiformes. The main diagnoses of confuciusornithids are as follows: both upper and lower jaws are toothless; the deltopectoral crest of humerus is large; and the major finger claw is extremely smaller than those of the alular and minor fingers. By now, our knowledge of the confuciusornithids mainly concerns their morphology and systematics, the evolution of the temporal region of the skull, and the diet and flight of early birds. Further scientific implications need to be explored not only in the abovementioned aspects, but also in other fields, considering both the quantity and preservation of confuciusornithids that excel among early birds.
