Keyhole & Lock

The symbol of the keyhole reminds of an ankh without arms. There is just a nub of one out to the side. And the smaller mound structures would seem to indicate a need for maturing or development. There are, of course, some fertility idols that are portrayed without arms and the arms of the Venus de Milo were likely purposely destroyed.  They could be generally people shaped but there is also a sense of landing pad or a gathering space in the circular part of the shape. These could also be windows or gateways into other dimensions. The shape also reminds me of a mirror with handle.