According to a myth, what insect defies physics?

The bumblebee flight myth: the idea that engineers have proved that bumblebees can't fly, or that bumblebee flight is not consistent with known aerodynamics is extremely well known. The idea is that bumblebee's wings are too small for that size of their bodies. Since they do fly, there is obviously something interesting going on - bumblebees can generate more lift from their wings than conventional aerodynamics methods should allow. They must be using some unconventional aerodynamics, if we can exploit the same aerodynamics we might be able to shift more air with smaller wings or propellers.