Currently viewing the category: "Marsh Flies and Snail Killing Flies"
What's That Bug? does not endorse extermination

Subject: Is this a fly?
Location: Mechanicsburg, PA
July 15, 2017 8:22 pm
Hi Bugman!
This guy was hanging out on our deck railing this afternoon. It’s a new one for me and I’d love to know what it is. I’m pretty good about looking things up, but I’m stumped and need the experts. It has fly looking eyes, but those wings are unique. It wouldn’t be a peacock fly with its wings down, would it? (One of those stopped by a couple years ago. First and only sighting.) It was the size of a lightning bug.
Signature: Perplexed in PA

Marsh Fly

Dear Perplexed in PA,
We believe this unique looking fly is a Marsh Fly,
Euthycera arcuata, thanks to this BugGuide image.  According to BugGuide:  “‘Very distinctive species with a unique closed-wing shape.’ –Bill Murphy.”  Of the family, BugGuide notes:  “adults around marshes, lakes, ponds, or wooded areas; larvae are aquatic” and “larvae parasitize or prey on freshwater or terrestrial snails.”

Thank you so much! That definitely looks like a match! We do have boggy/marshy areas near our house and I’ve seen snails in certain areas of our yard. That’s so interesting. Some bugs are familiar and easy to spot – seasonal regulars. Others are chance encounters never to be seen again. I love discovering what’s right in my own backyard!

What's That Bug? does not endorse extermination

Subject:  Friendly fly from Manitoba
Location:  Pacey Lake, Manitoba, Canada
June 12, 2016
Hi Daniel.  I haven’t posted on this site for a while, so I thought I might share this one that I photographed a few days ago. The ‘smiley face’ image is a surprisingly common theme in insect decoration; especially if you have an active imagination. This, however, is by far the most perfect and obvious that I have ever seen. It’s a Marsh Fly (Sciomyzidae: Tetanocera plebeja), sometimes called snail-killing flies because their larvae are parasitoids of snails. Cheers. Karl

Marsh Fly

Marsh Fly

Hi Karl,
We were away from the office when you sent your wonderful image.  There was no Marsh Fly category on the site, so a new category was created to accommodate your awesome image of a smiley faced Marsh Fly.  According to BugGuide:  “‘Noting the pattern on the wings is the quickest means of determining this common and widespread species.’ — Bill Murphy”

What's That Bug? does not endorse extermination