Sinopterus

Sinopterus is a genus of tapejarid pterosaur from the Early Cretaceous of China. Fossils have been found in the Jiufotang Formation of northeastern China, which dates to roughly 125 to 120 million years ago. The genus is one of the better-known Chinese tapejarids and helps illuminate the early diversity of this group.

Anatomy and appearance typically associated with Sinopterus includes a short, broad skull and a toothless or nearly toothless beak, features common to tapejarids. Many specimens display a cranial crest, the size and shape of which can vary among individuals. As with related taxa, the body plan would have supported a relatively large head in proportion to the torso, and wings adapted for soaring.

Taxonomy and species within Sinopterus have been subject to considerable debate. The genus was established to accommodate distinct jiufotang pterosaur fossils, and numerous specimens described over the years have been reassessed. As a result, the number of valid species and even the boundaries between Sinopterus and related genera remain unsettled in modern reviews. Nonetheless, Sinopterus is widely cited as an example of early tapejarid diversity in Asia.

Paleoecology and significance: Sinopterus inhabited Early Cretaceous environments in what is now China and contributes to understanding the geographic spread and evolution of Tapejaridae. Its fossils, along with other contemporary pterosaurs, help illustrate the ecosystem dynamics and morphological experimentation occurring among pterosaurs during this interval.