Pedopenna daohugouensis

Pedopenna is the largest predator found in the Tiaojishan formation thus far, though it is roughly tied with Xiaotingia zhengi for that title.
The name means ''Daohugou's foot feather'' and is called that way, because it was found in the Daohugou beds and the only known specimen is a leg with very large feathers on the metatarsus.

It is quite nicely preserved, but very fragmentary because it's just one leg.
But that's enough to discern that it was a basal avialan theropod, with a length of roughly 1 meter, (3,3 feet).
1m doesn't sound like much, and objectively speaking, it is a really small theropod, but you should see it's size in context.
The Tiaojishan formation has so far only yielded very small animals, with most being under 500 grams heavy, so Pedopenna suddenly becomes a lot more imposing.
Though, this reasoning isn't entirely correct: it is well known that the Tiaojishan formation has a very strong bias towards smaller animals, so large animals rarely or never get preserved in it's fine lacustrine and ash sediments.
Large animals simply couldn't be covered soon enough by the fine and light sedimentation of the lakes here.

Considering the temporal span and the geographic location, the Tiaojishan formation's large animals (which we haven't found yet) were likely metriacanthosaurids, megalosauroids, mamenchisaurs, Shunosaurus-like sauropods, basal stegosaurians and small-ish ornithopods.
All of these groups are represented in the chronologically similar Dashanpu formation, which mostly preserves large animals instead of small ones.

Regardless of that, Pedopenna was a fleet-footed predator of small animals.