Jaculinykus (meaning "Jaculus claw") is an extinct genus of alvarezsaurid theropod dinosaur from the Late Cretaceous Baruungoyot Formation of Mongolia.

[1] The Jaculinykus holotype specimen, MPC-D 100/209, was discovered in sediments of the Baruungoyot Formation (Nemegt locality), of Ömnögovi Province, Mongolia.

[1] In 2023, Kubo et al. described Jaculinykus yaruui as a new genus and species of parvicursorine alvarezsaurid based on these fossil remains.

The cladogram from Kubo et al. (2023) is shown below:[1] Aorun Haplocheirus Xiyunykus Tugulusaurus Bannykus Patagonykus Achillesaurus Alvarezsaurus Albertonykus Qiupanykus Nemegtonykus Dzharaonyx Khulsanurus Linhenykus Parvicursor Ceratonykus Xixianykus Albinykus Ondogurvel Mononykus Jaculinykus Shuvuuia Fossils of Ondogurvel, another parvicursorine alvarezsaurid, as well as fossils of Nemegtomaia, an oviraptorosaur, are also known from the Nemegt locality of the Mongolian Barun Goyot Formation.

[2] Other localities from the formation have yielded dinosaurs including additional alvarezsaurids (Ceratonykus, Khulsanurus, and Parvicursor),[1] as well as dromaeosaurs (Hulsanpes,[3] Kuru, and Shri[4]), oviraptorosaurs (Conchoraptor and Heyuannia),[5] a sauropod (Quaesitosaurus),[6] ceratopsians (Bagaceratops and Breviceratops),[7] a pachycephalosaur (Tylocephale),[8] and ankylosaurs (Saichania,[9] Tarchia,[10] and Zaraapelta[11]).