So I find these flies every year in my mulch, and I've never seen them anywhere else. The mulch becomes full of their larvae, which I feed to my toad and lizards. There are so many that you can hear them moving. The adults are black, look like a wasp or hornet, and have a curious green patch on the underside of their abdomen, which is a clear patch showing some kind of liquid. The larvae are brown and have a little hair on them.

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It's about one inch I think maybe a little less. I hope the quality is good enough, because I used my iPod for the picture and you can't do macro with it. Also, I live in Hillsboro Oregon. I am near a small forest and in the suburbs.

  • 3
    $\begingroup$ A picture (but I think you need more reputation first so I've upvoted) and location would both be very useful for this. also some idea of size. $\endgroup$
    – rg255
    Sep 2, 2013 at 6:12
  • $\begingroup$ Hi Keivn, to show us the pictures you have first upload them to a website such as imgur.com and edit your post to include the links the site gives you. Once you have 10 reputation you will be able to this in one step on this site. $\endgroup$
    – Rory M
    Sep 2, 2013 at 12:04
  • $\begingroup$ You now have more than 10 reputation and can include images in your post. $\endgroup$
    – terdon
    Sep 2, 2013 at 13:29
  • $\begingroup$ This should be a comment, but rep is too low. Question: what do you put in your mulch pile? That would help ID the fly. $\endgroup$
    – dmm
    Sep 26, 2013 at 21:44
  • $\begingroup$ These links might help: Wasps and BugGuide. $\endgroup$
    – Pradeep S
    Sep 26, 2013 at 22:58

1 Answer 1


Black soldier fly Hermetia illucensBlack soldier fly.. http://en.wikipedia.org/wiki/Hermetia_illucens

There is a good key to the Dipteran families here. Although it is for British families, it is very thorough.


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