Insect and Spider Identification: CLOSED: Help me ID this fly, please, 1 by debnes_dfw_tx

debnes_dfw_tx wrote:
This is a tiny fly that is often mistaken for an ant. It sucks the life out of caterpillars and chrysalids left outside. Even screen will not keep them from destroying butterflies. They are so small they can crawl through standard sized window screen squares.

The mesh holes in this photo are half the size of ordinary window screen squares, and the little fly is almost small enough to squeeze through. So far it works to keep them out...Meanwhile, exactly what are these things?


Thanks!