Extra vertex shapes

[Turgon-Aran-Gondolin]

Is there extra vertex shapes other than dot, square dot, empty dot, crossed dot and blob? If there's none, is it possible to add more?

An additional question if you can't add more shape for now:
How to define a new vertex shape which is the overlay of two pre-existing shapes? i.e. use something like

\tikzfeynmanset{
            empty square dot/.style={
                %1st shape
                /tikzfeynman/square dot,
                /tikz/black,
                %2nd shape
                /tikzfeynman/square dot,
                /tikz/minimum size=0.7mm,
                /tikz/white,
            },
}

my example clearly won't work tho.