The group was first formally proposed by Choiniere and colleagues in 2010, to contain the family Alvarezsauridae and non-alvarezsaurid alvarezsauroids, such as Haplocheirus,[2] which is the basalmost of the Alvarezsauroidea (from the Late Jurassic, Asia).

The basalmost and oldest alvarezsauroid of the Chinese alvarezsaurs is from the Shishugou Formation in Xinjiang (earliest Late Jurassic).

[2] But this association was reevaluated after the discovery of the primitive forms like Haplocheirus, Patagonykus and Alvarezsaurus, which do not show all bird-like features as the first discovered species Mononykus and Shuvuuia.

More recently, they have been placed within the Coelurosauria basal to the Maniraptora or as a sister taxon of Ornithomimosauria within the Ornithomimiformes.The cladogram below is the latest and most comprehensive analysis of alvarezsaurian evolution, following Meso et al.

[6] Shishugounykus inexpectus Aorun zhaoi Haplocheirus sollers Bannykus wulatensis Xiyunykus pengi Tugulusaurus faciles Alnashetri cerropoliciensis Bonapartenykus ultimus Patagonykus puertai Achillesaurus manazzonei Alvarezsaurus calvoi Ceratonykus oculatus Khulsanurus magnificus Qiupanykus zhangi Dzharaonyx eski Linhenykus monodactylus Parvicursor remotus Shuvuuia deserti Mononykus olecranus Ondogurvel alifanovi Albinykus baatar At first, alvarezsauroids were thought to have been originated in South America.

They instead found that statistically significant biogeographic reconstructions suggest a dominant role for sympatric events (“within area” ones), combined with a mix of vicariance, dispersal and regional extinction.

The Asian origin of alvarezsauroids is also bolstered by the discovery of alvarezsaurid specimens from the Turonian-age Bissekty Formation (some of which were named Dzharaonyx in 2022[8]) of Uzbekistan and Bannykus, Tugulusaurus, and Xiyunykus from the Early Cretaceous of China.

[5] In contrast to the digit reduction of the hand of derived alvarezsauroid to a claw used for digging, Haplocheirus was still able to grab things.

While alvarezsauroids show a simplified homogenous dentition, Haplocheirus on the other side possesses recurved serrated teeth.