Bonapartenykus resided in what is now Patagonia, Argentina, roughly 70 million years earlier (Cretaceous duration ).

Explained in 2012, this dinosaur belongs to one of the most mystical groups of dinosaurs, called the Alvarezsauridae.

With another Patagonian genus, Patagonykus Bonapartenykus kinds a little alvarezsaurid clade, the Patagonykinae.

“Alvarezsauria is a group of later-diverging coelurosaurian theropod dinosaurs of medium to little size, whose fossil record covers from the Late Jurassic to the Late Cretaceous,” stated Universidad Nacional de Río Negro paleontologist Jorge Gustavo Meso and coworkers.

“The circulation of this clade was most likely initially Laurasian considering that its earliest recognized members are presently limited to the Oxfordian (Late Jurassic) of China.”

“The Early Cretaceous fossil record of Alvarezsauria was likewise restricted to the Asian continent, which now includes as much as 3 types.”

“By the Late Cretaceous, Alvarezsauria was extremely diversified and internationally dispersed, with plentiful Laurasian records from what is now Asia, Europe, and North America along with the very first Gondwanan records represented by discoveries from South America.”

“Patagonykinae is the just called South American clade of alvarezsaurids that clusters Patagonykus and Bonapartenykus“

In their brand-new research study, Dr. Gustavo Meso and co-authors analyzed a great deal of alvarezsaurid fossils from the Salitral Ojo de Agua area of the Patagonian Allen Formation.

“Although these specimens were gathered at various times without accurate initial provenance info, we collected X-ray diffraction information of the associated sediments that now recommends that all of these specimens originate from the very same website and stratigraphic level as the holotype of the alvarezsaurid Bonapartenykus ultimus,” the paleontologists stated.

“Based on this brand-new provenance info and the morphological resemblance of the thought about specimens, we tentatively refer them to the genus Bonapartenykus“

According to the authors, the newly-described specimens clarified the body strategy of Patagonykinae by allowing a more total restoration of their neck, pectoral girdle, hindlimb, and tail.

“While our outcomes prefer a monospecific alvarezsaurid assemblage for the minute, future research study and quarrying efforts at the Salitral Ojo de Agua region might discover proof that can even more evaluate our existing analysis,” they stated.

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J.G. Meso et al2025. New details on Bonapartenykus (Alvarezsauridae: Theropoda) from the Allen Formation (middle Campanian-lower Maastrichtian) of Río Negro Province, Patagonia, Argentina clarifies the Patagonykinae body strategy. PLoS ONE 20 (1 ): e0308366; doi: 10.1371/ journal.pone.0308366