Surely, many of you have seen these animals flutter in the field… And surely many of you have turned away when you saw them nearby and shouted: “Watch out, a wasp!”
Well, they’re actually flies… yes, harmless FLIES known as syrphid flies, flower flies or hoverflies. They imitate the coloration of wasps, which warns of their danger.
In biology this is called mimicry and is a type of defense. In this case it is called Batesian mimicry, since the mimetic (the fly) is not toxic, while the model (the wasp) is.
And now you’re wondering… HOW CAN I DIFFERENTIATE THEM?
While they are flying it is a little difficult, although the flight of the syrphids is a bit different. Some clues:
Wasps have 4 functional wings, while hoverflies are diptera, so they have only 2 functional wings.
Hoverflies have huge compound eyes, large in relation to the size of the head, like those of the common flies. Quite different from wasps.
The antennae of hoverflies are much smaller than those of wasps.