This is a giant, virus-infected, disease-spreading, lymph-sucking mosquito.
Well, no, it isn't. It is only a crane fly. But, crane flies indeed resemble huge, parasite-infected, brain-inflaming, blood-sucking mosquitos, although in reality they don't even bite and are totally harmless, at least to photographers. They seem to be rather weak fliers and are quite easy to catch by hand.
Based on the venation of its wings, I have identified this individual as a Tipula sp.
Their larvae are mostly aquatic and feed on small children. Okay, maybe they don't do that either.