they are based on mantises right?
mantises literally have 12+ month lifespans, and since they have biological organs to support a larger size like a skeleton, extra muscles, lungs and heart, etc, that would also greatly boost their lifespan to that of a human more, coupled with them also living on a non hostile environment as well making it easier to live beyond than expectations [well before the viltrumites arrive and turn them into sex slaves]
and plus they are an interstellar race or semi because they have vehicles that can travel to earth within a week or less, wouldnt that mean they would also have the technology to also boost their lifespans to?
still there couldn’t be any means for other methods to extend their lifespans if they can reach to interstellar levels of travel then im sure there’s some form of tech to extend their lifespan as well.