What is the hevyest insect?

There isn't actually a clear-cut answer to this. The heaviest any insect ever gets is around 120g, achieved by the goliath beetle in its larval stage. For adult insects, the heaviest is probably an elephant beetle, as they very often exceed 60g. Nevertheless, the heaviest recorded is not an elephant beetle, but a freakishly large giant weta, recorded at a whopping 71g.