Logging onto Yosemite with FileVault enabled with no username displayed?

When I log onto my Mac with FileVault enabled, I am prompted for the user/pass prior to the OS loading, as my boot drive is encrypted.

The problem I have is that, counter-intuitively, it always shows my name as the login user! I just want blank fields that ask for the username and password respectively, not a prompt for my password.

Does anyone know how to fix this?

Edit: This is a screenshot of how Users & Groups is configured: