Greater wax moth larvae can tunnel and feed to the midrib of the wax comb. The midrib is the base of the comb on which the cells are constructed. The feeding larvae produce silken threads that can trap developing honey bee brood in the cells. Trapped bees will uncap their brood cell when ready to emerge as adults but will be unable to emerge. The result is a comb containing uncapped bees that struggle to emerge, a condition called galleriasis. Williams (1997) states that “entire combs of worker bees that have developed from brood of nearly the same age may be observed trapped in this way”.