To list all toppings for pizza is impossible as the list is only restricted to the restrictions imposed by your imagination. Even popular pizza toppings are not easy to categorize when the Americans prefer pepperoni and the Japanese favor squid.
Having said that prefered pizza toppings are individual, I have attempted to compile a list of pizza toppings without using esoteric marshmallow and squid ink! Pizza is so universal that a pizza chef somewhere will have added every type of food known to man on a pizza, for sure an Aborigine will have popped a witchetty grub on a pizza somewhere, the witchetty grub being the larvae of the ghost moth. Equally a Thai pizza chef will have used green ants at some time. Crickets are a delicacy in Burma .
Whilst I regard it as unlikely that a chef has not combined all of these three toppings on a pizza I am not going to put any money on it! Should any one want to try to put green ants on the pizza they are better as a garnish they should never be cooked it destroys the Vitamin C and it as their Vitamin C content that makes them a valuable food source.