Are you sure the translation of the title is correct? I mean if it is what it says then it is what it says, but the flies that evolve out of antlions aren't mayflies.
Mayflies have aquatic larvae and once they are flies they lose their mouth, which is why they only live one or two days, they mate and starve to death. In most species of mayfly the larvae moult once to leave the water and then they molt again in order to become the mayfly, at which stage they loose their mouth but in return gain the ability to fly and their reproductive organs get fully developed.
Antlions on the other hand turn into something that is called an "antlion lacewing" or simply "adult antlion" and in comparison to mayflies, they still have a mouth an live for longer then a few days and depending on the species either feed on nectar or other insects.
