" Scansoriopteryx heilmanni" (and its likely synonym "Epidendrosaurus ninchengensis") was the first non-avian dinosaur found that had clear adaptations to an arboreal or semi-arboreal lifestyle–it is likely that they spent much of their time in trees. Both specimens showed features indicating they were juveniles, which made it difficult to determine their exact relationship to other non-avian dinosaurs and birds. It was not until the description of "Epidexipteryx hui" in 2008 that an adult specimen was known. In 2015, the discovery of another, larger adult specimen belonging to the species "Yi qi" showed that scansoriopterygids were not only climbers but also had adaptations that could have been used for gliding flight. The recently discovered (in 2019) "Ambopteryx" also proves this. The earlier describbed "Pedopenna" may also be a member of this clade.