Friday mystery object #138

Postcranial bones are found more often than skulls, but they can be harder to identify since they don’t have such diagnostic characteristics (like teeth). So, any idea what this piece of postcranial skeleton is and what it comes from?

As usual you can put your answers below and I will do my best to respond (within my technological and temporal constraints). I’m sure some of the other biology types will be willing and able to give guidance. Good luck!