Shu Xilong fossils are found in sedimentary rocks of continental lakes, and other fossils in the same place include a large number of amphibians and polychaetes. Although scientists have not yet reached an agreement on the geological age of these rock formations, most scholars believe that their age is earlier than the early Cretaceous strata in western Liaoning, which produced a large number of birds and hairy dinosaurs, and it is likely to belong to the late Jurassic.

Shu Xilong's specimen represents a small individual. If you don't consider its long tail, it is only as big as a sparrow. Its most peculiar feature is that the third finger is much longer than the other two fingers, which is different from any other known dinosaurs and birds. Although the function of this super-long finger is not very clear, it is certain that this creature is a species adapted to living in trees, because not only the third finger of Shu Xilong is long, but also the second finger (toe), second finger and toe (the second finger or toe from the end) of its forelimb are relatively long. These are the characteristics of adapting to life in trees.

In addition, the distal ends of Shu Xilong's first to fourth metatarsals are almost at the same level, which is very similar to many modern birds that are particularly adapted to living in trees, further proving its ability to live in trees.

Interestingly, some arboreal features of Shu Xilong are more advanced than the most primitive bird archaeopteryx recognized in the world at present. This seems to indicate that the initial tree life of some theropod dinosaurs may be more related to finding food and avoiding being hunted than directly related to flying. Shu Xilong's life time and its characteristics suitable for tree life also show that theropod dinosaurs began to live in trees as early as the early Cretaceous, before birds multiplied in large numbers. This discovery makes the hypothesis that birds originated from dinosaurs more perfect and further supports the arboreal origin theory of bird flight. The ancestors of birds are more likely to be groups living in trees than groups running on the ground.

On August 27th, 2002, China ivpp Zhang Fucheng and other experts published a paper in Naturwissenschaften (2002, 89: 394-398), describing a coelomosaur living in trees and naming it epidendrosaurus.

But now there is controversy about the validity of scientific names. The paper published by czerkas, S.A. and c.yuan through another specimen (network paper) describes that the publication date of scansoriopteryx heilmanni is 1 August, which is a valid name according to the naming priority principle.

However, experts such as Zhang Fucheng retorted that researchers who are good at climbing birds and dragons didn't send them a fax notice until August 26-29, so it was impossible to publish it on August 1 day. The most serious thing is that the specimen of the reptile is of unknown origin, and it is likely to be smuggled. According to international practice, smuggled specimens cannot be studied and published.

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