Struthiomimus or Nano?

[Pterosaur]

Hi everyone!

 

I have another puzzle for you all! I REALLY appreciate your help identifying these bones, and even though I may never know what they really came from it is so interesting to propose and discuss possibilities. 

 

The majority of the bones I found this summer (in Montana) were really odd and hard to identify... They all came from roughly the same 5'x5' spot in the same formation. 

 

Anyways, this one is no doubt theropod. It's beautiful with awesome preservation aside from the whole 'missing an entire side' thing. Hopefully you can help me out!

 

Thanks so much! More to come... ☺️

-Lauren

 

P.S. Sorry for the white spots. Had to put it back together and haven't painted yet.