Why there isn't a symbol that represents Socialism?

While Communism has a very well known and used symbol (hammer and sickle), Socialism doesn't.
Even though Communism and Socialism are somewhat similar they aren't the same, so why doesn't Socialism have a symbol (or if it does, which could be one).
I also thought that the communist symbol purely derived from the USSR flag and that made me think that also other symbols like these came from flags (like the 3rd Reich for Nationalsocialism), but with Capitalism we can somehow imagine one (even though there isn't any specific in flags eccetera.