Found this Rubber pulley ring doing oil change?

[quadzilla200]

Not sure how to describe it other than that. It appears to have fallen off along with another piece that became unglued? That piece is gone.
Any advice on what part I replace if needed.

 

[Glasman888]

That's the harmonic balancer ring. The rubber fails, letting the outer ring slip. Don't drive it. You need a new crankshaft pulley/harmonic balancer. Get it fixed asap before it comes apart completely.

 

[NC356]

On my 2016 3.8, that would be the A/C compressor.