Missing piece by gear shifter

[lmb123]

This is driving me absolutely crazy, because I can't figure out what it is to get a replacement part.  There is a small square next to the gear shifter that I can tell should have a cover on it.  Does anyone know what this thing is called so I can find a replacement cover for it?  2013 Lexus RX 350.  This photo has the thing I'm talking about circled, but it has a cover on it.  

[dsvetcov]

I have heard it termed the 'small square pad next to the shifter'   It allows access to the 'shift interlock system.  

[lmb123]

Thank you!