March Fly, NOT Stiletto Fly

Subject:  unknown insect
Geographic location of the bug:  Lynnwood
Date: 04/06/2018
Time: 01:12 PM EDT
Your letter to the bugman:  I found several of these insects on the emerging leaves of a red currant.  Can you tell me what they are and whether they are innocuous or harmful?
How you want your letter signed:  Nancy Wyatt

March Fly

Dear Nancy,
We believe this is a Stiletto Fly in the family Therevidae, and according to BugGuide:  “Adults are nectar feeders; larvae prey on soil arthropods.”  Several species are pictured on Natural History of Orange County, but none looks exactly like your individual.  ResearchGate has some images of Australian Stiletto Flies that look similar to your individual.  We hope to get a second opinion on our identification.

Wow, that was fast!  I’m sure you’re right about the identification.
I do so much appreciate your interest and expertise.  And I gained more knowledge about my insect neighbors.
The fly larvae can eat all the soil arthropods they like from my garden!

Eric Eaton provides a correction:  March Fly
Sorry, I am “out of the office,” hence the delay in replying.  This is a dance fly, probably genus Empis.  Probably female, too.  Pretty common early spring flies in the Pacific coast states.
author, Kaufman Field Guide to Insects of North America

Ed. Note:  Once Eric Eaton provided us with a genus name, we did find this individual from Ireland posted to Alamy and this individual from California posted to BugGuide.

Well, that sounds a lot more peaceful than “stiletto fly”.  I either case I don’t have to worry about the larvae eating my currant plants.  It’s a real struggle saving them from the aphids in the spring. I’m so impressed that you and your colleagues would provide this service, which I have bookmarked and will recommend to all my friends in the gardening community here.

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