Motherboard part fell off

[TotalNoobBuilder]

So today a piece of my motherboard fell off as I lifted it up to attach the backplate for a closed loop CPU cooler, there are many sockets just like this one, and I had just taken the mobo out of the box before this fell off, I have no idea why it would do so. I have no clue what it's purpose or importance is... please help, pic above. I have an asus Maximus IX Code mobo. I've done a test boot out of the case, and everything works just fine but it still worries me.

 

[Mister_MO]

On motherboard from backside should be 3 more of there screws. These looks like they hold those plastic armor pieces. So nothing needed for functionality.