Probable microraptorian ichnotaxon Dromaeosauriformipes was discovered from the Jinju Formation of South Korea,[3][4] and some fragmentary Late Cretaceous paravian fossils in North America have been described as putative members of this clade.
[5] Most microraptorians were relatively small; adult specimens of Microraptor range between 77–90 centimetres long (2.53–2.95 ft) and weigh up to 1 kg (2.2 lb), making them some of the smallest known non-avialan dinosaurs.
Some fragmentary paravian fossils from the Late Cretaceous (Campanian-Maastrichtian stages) of North America have been putatively suggested as microraptorians, though their taxonomic referral are considered controversial, namely Hesperonychus being recovered as an avialan in one phylogenetic analysis.
[18] Senter and colleagues expressly coined the name without the subfamily suffix -inae to avoid perceived issues with erecting a traditional family-group taxon, should the group be found to lie outside the Dromaeosauridae proper.
[19] Sereno offered a revised definition of the subgroup containing Microraptor to ensure that it would fall within the Dromaeosauridae, and erected the subfamily Microraptorinae, attributing it to Senter et al., though this usage has only appeared on his online TaxonSearch database and has not been formally published.