Transverse-banded Flower Fly

Where there are flowers, these Transverse-banded Flower Flies can sometimes be seen. Like all syrphid flies (aka flower flies and hover flies), these are true flies (unlike fireflies, who are secretly beetles, or butterflies or dragonflies, that are completely different insects). 

If you have a garden and hate being stung, these flies are right up your alley. As adults they're all about nectar, pollen, and honeydew, are incapable of stinging, and apparently don't bite. And while butterflies also meet those criteria, these flies have an additional benefit. As kids (aka larvae) they'll eat some garden pests like aphids.

They are also a classic example of Batesian mimicry since they look dangerous but aren't. I'm not exactly sure who they're trying to mimic though:

  • Their color and shape could fool a predator into thinking they're bumblebees.
  • Their color and lack of fuzziness could fool a predator into thinking they're yellowjackets.
Perhaps they're mimicking both? Would a robin look at one and think: "I've been stung by bumblebees and I've been stung by yellowjackets. I think I'm going to stay away from that bumblebee/yellowjacket hybrid (bumblejacket) thing."? Whatever they're mimicking, it seems to be working for them since this is a fairly commonly spotted flower fly. (And if you think you've never seen one, just how closely have you looked at bumblebees and yellowjackets that you've encountered?)

September 24, 2021 at Duke Farms
Photo 168287684, (c) jpviolette, some rights reserved (CC BY-NC)


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