Summer Fishfly, we believe

Identification Request: not a Dobsonfly but what?
Location: Stillman Valley, IL
May 15, 2012 9:33 am
Hello Bugman,
Long time fan Amy B. here..I noticed this not so little guy on my screen this morning. At first I thought I was looking at a male Dobsonfly, but then I noticed the ”feathery” antennae so that made me second guess myself. What is it?I looked around a bit to try to find it, but the baby is keeping me from doing very much searching. There is one photo with the corner of our newspaper in it to give an idea of scale..I’d say it was about an inch and three quarters with the antennae. I live in northern Illinois near a creek. Let me know when you get a minute, would ya? Sincerest thanks!
Signature: Huge fan of the site

Summer Fishfly

Dear Amy,
Thank you for your kind compliments.  Your confusion is easily explained.  We believe this is a Summer Fishfly,
Chauliodes pectinicornis, and it is closely related to the Dobsonflies which are in the same family Corydalidae.  According to BugGuide:  “Both sexes have pectinate antennae. Flies, probably, more in mid to late summer than the more spring-flying C. rastricornis. Head and pronotum have yellow markings on dark brown background, compared to dark markings on yellowish background in C. rastricornis.”  The description is closer to the Summer Fishfly, though the sighting in May tends to indicate this might be the closely related and very similar looking Spring Fishfly, Chauliodes rastricornis, which is also profiled on BugGuide.

Thanks so much! I had come to the same conclusion during a nap the baby was taking that allowed me to search a little more. I’ve never seen anything related and always had hoped to see a Dobsonfly in person especially after seeing how big they get in some of the pics. This guy stayed on the screen all day until the sun set and then took off for his own adventures. It was a pleasure to have his company for the day and I was honored. Thanks again Bugman for all the work you do in keeping us in the know!!
Very sincerely,
Amy Berogan

3 thoughts on “Summer Fishfly, we believe”

  1. My husband saw this hugh bug with about a 3 inch wing span yesterday. Today, after a rain he found it on the sidewalk, dead. Since we have never seen one like it before in southern Missouri I checked the computer. This bug is 3 1/2 inches long from front tentacles to tail end, has cross over wings, light colored, (almost translucent) with dark markings. It looks like the bug pictured.


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