QListView QCss styling of selected/checked item inside QComboBox

[perry_blueberry]

I have a QComboBox. By default the previously selected item has the checkmark and is bold. I'm trying to set the style of this item while leaving the hovered item as is. The problem is that I cannot find the right QCss selector to access it. I've tried QListView::item:selected which selects the currently hovered item, QListView::item:checked which doesn't select any item.
Which selector should I be using? And where can I find a list of all the selectors available?