The first pterosaur basihyal, shedding light on the evolution and function of pterosaur hyoid apparatuses

PeerJ

article

Shunxing Jiang¹  Zhiheng Li¹  Xin Cheng³  Xiaolin Wang¹ 

[1] Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences;CAS Center for Excellence in Life and Paleoenvironment;College of Earth Sciences, Jilin University;Laboratório de Paleontologia, Universidade Regional do Cariri;College of Earth and Planetary Sciences, University of CAS

关键词: Pterosaurs;    Basihyal;    Hyoid apparatus;    Evolution;    Function;    Yixian Formation;    China;   

DOI  :  10.7717/peerj.8292

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

The pterosaur is the first known vertebrate clade to achieve powered flight. Its hyoid apparatus shows a simplification similar to that of birds, although samples of the apparatus are rare, limiting the ability to make an accurate determination. In this study we reveal a new pterosaur specimen, including the first definite basihyal. Through the comparison of pterosaur hyoids, a trend has been discovered for the shortened hyoid relative to the length of the skull, indicating a diminished role of lingual retraction during the evolution of the pterosaur. The new material, possibly from a gallodactylid Gladocephaloideus, represents one of the least effective lingual retractions in all pterosaurs. Based on the structure of an elongated ceratobranchial and retroarticular process on mandibles, the function of the Y-shaped istiodactylid tongue bone is similar to those of scavenger crows rather than chameleons, which is consistent with the interpretation of the scavenging behavior of this taxon. More fossil samples are needed for further study on the function of other pterosaur hyoids.

【 授权许可】

CC BY