Currently viewing the category: "Tachinid Flies"

Subject:  Found a Belvosia
Geographic location of the bug:  Burnham Maine, Waldo County
Date: 08/28/2021
Time: 01:48 PM EDT
Your letter to the bugman:  Finally I was pruning one of my flowering bushes and my daughter and I came across this huge fly but it looks like a bee I’m like it looks like a crossbreed between a fly and a bee and she said yeah it does so I looked it up because I have Google lens on my phone and it said it was a Belvosia and then I found some articles stating that they’ve also been sighted in Clinton and Fairfield Maine which I lived in Clinton too so I wanted to submit a few pictures that I took to you
How you want your letter signed:  Bobbie Jean

Tachinid Fly

Dear Bobbie Jean,
Congratulations on successfully identifying your Tachinid Fly in the genus
Belvosia.  Thank you also for submitting your excellent images.  According to BugGuide they feed on Lepidoptera.  The female Tachinid lays her eggs on a caterpillar and the fly larvae parasitize the caterpillar.

Tachinid Fly

Subject:  Maybe a tiger bee fly?
Geographic location of the bug:  Louisville, KY 40299
Date: 07/20/2021
Time: 11:00 AM EDT
Your letter to the bugman :  Good day sir, this (not so little) guy was hanging out on my front porch and wasn’t too disturbed by me getting my phone very close for these striking images. I placed a penny near it in a couple of photos so you could have a sense of scale. Wondered what exactly it is and if it is dangerous in any way. Thanks kindly!
How you want your letter signed:  Wayne H

Tachinid Fly

Dear Wayne,
Daniel just published an identification request for a Tiger Bee Fly, which is definitely not your fly.  This is actually a Parasitic Tachinid Fly in the family Tachinidae, a group with many individuals that are covered with course hairs, so they are sometimes called Bristle Flies. Your individual appears to be a member of the genus 
Leschenaultia which is pictured on BugGuide where the host prey is identified as members of several moth families. Insects that are parasitoids, meaning the eggs are laid on the bodies of host insects which are eaten alive, are often very specific about the host prey which is sometimes limited to a single species.  This fly poses no threat to humans.

Tachinid Fly

Thank you so much for the information!
Wayne Hutchins

Subject:  You’re Bristle Fly post
Geographic location of the bug:  Southern Yorke Peninsula S.A
Date: 06/05/2021
Time: 09:25 PM EDT
Your letter to the bugman:  I took these photos in a Flora Park on the 27th of Dec. 2020 in Edithburgh. My home town. Interesting to see all your varieties. I just thought it was beautiful, like a piece of jewellery, all golden.
Only ‘just’ learnt it was a fly– 2 wings.
Please respond with the fly’s official name. Would like to have this submitted in the local newsletter. The photo was taken on my Samsung S5.
Thank you for your time.
How you want your letter signed:  Mrs Charyl Turner

Bristle Fly

Dear Charyl,
We believe your Bristle Fly is
Formosia speciosa.

Subject:  Black fly, yellow stripe on head
Geographic location of the bug:  Westfield, MA, USA
Date: 07/11/2020
Time: 01:47 PM EDT
Your letter to the bugman:  We have a hybrid hydrangea that blooms through July.  Some days there are many dozens of insects enjoying the blooms.  I cannot identify this one.
How you want your letter signed:  Steveb

Featherlegged Fly

Dear Steveb,
This is one of the parasitoid Tachinid Flies in the genus
Trichopoda which are known as the Featherlegged Flies, and it is probably Trichopoda lanipes which is pictured on BugGuide.  According to BugGuide, it preys on Leaf Footed Bugs in the family Coreidae.

Subject:  Karner blue butterfly
Geographic location of the bug:  Albany Pine Bush, Albany, NY
Date: 05/27/2020
Time: 05:43 PM EDT
Your letter to the bugman:  Hi What’s that Bug!
Here’s a mystery for you. I’m quite certain this is a Karner blue butterfly, Plebejus melissa samuelis. You may be aware that our Albany Pine Bush in upstate New York is one of the few habitats this endangered subspecies can thrive, since its larvae feed only on the wild blue lupine that grows here. I saw quite a few Karner blues out among the lupines on this visit! None of our other local blues have that much orange along the wing, so it has to be a Karner.
The mystery: what the heck is going on with its abdomen? What is that orange stuff at the end? I thought it might be laying an egg, but as far as I can tell their eggs are light gray or white, not orange. And anyway it’s not on a lupine–I think the plant is a raspberry or blackberry. It stayed in this position for a couple of minutes before fluttering off, and I didn’t realize there was anything weird until I looked at the photos.
I’ll also include a better image of a different individual for your enjoyment. This little guy seemed to be more interested in lapping up my sweat than anything else–I tried to coax it onto a lupine, but it wouldn’t leave!
How you want your letter signed:  Susan B.

Male Karner Blue exposing his genitalia

Dear Susan,
Though we are quite excited to post your Karner Blue images, we will start with the mystery.  We don’t know what that is, but we suspect it is not a good thing.  We suspect this might be evidence of parasitism, possibly Dipteran, meaning a type of fly.  Though we don’t often site Wikipedia, it does provide this information “A tachinid fly,
Aplomya theclarum, has also been listed as a Karner blue butterfly parasite.”*  We will attempt to get a second opinion on this matter.  Meanwhile, we really are thrilled with your images of Karner Blues.  Not only was it described by one of Daniel’s favorite writers, Vladimir Nabokov, it is a new species for our site that currently contains over postings. 

Karner Blue

*Haack, Robert A. (1993). “The endangered Karner blue butterfly (Lepidoptera: Lycaenidae): biology, management considerations, and data gaps”. In Gillespie, Andrew R.; Parker, George R.; Pope, Phillip E. (eds.). Proceedings, 9th central hardwood forest conference; 1993 March 8–10; West Lafayette, IN. Gen. Tech. Rep. NC-161. St. Paul, MN: U.S. Department of Agriculture, Forest Service, North Central Forest Experiment Station. pp. 83–100.

Thank you so much for your reply! I was pretty excited to spot so many Karner blues that day—usually I don’t get out to the Pine Bush until later in the year, when they are scarcer. I’ll be going back early in the morning to see if I can catch them basking with their wings open.
That’s a good thought that the orange mass may be parasites. I hadn’t even considered that it could be somebody else’s eggs. I’ve sent the image along to the staff at the Albany Pine Bush to see if they can identify it for sure, and also so that they can document it, since they monitor all the happenings with the wildlife there.
Susan B.
Karner blue update—I heard back from the entomologist at the Albany Pine Bush regarding the weird orange mass on my Karner blue butterfly. Here’s her response (with her permission to share):
“Hi Susan,
Thanks for sending along the images! I have to tell you, what you are seeing there at the end of the abdomen is rated PG-13. What you captured is the genitalia of a male karner. They don’t usually flash them like that, it is unusual to see as they are usually kept internally until mating. An interesting thing to document, for sure! Thanks again for sharing.
Best,
Dillon”
What a relief to hear that I was only witnessing a bit of lepidopteran exhibitionism, and not a parasite infestation (fascinating though that would be)!
-Susan B.

Thanks for the fascinating update Susan.  It is interesting that Nabokov classified many of the Blues using a theoretical taxonomy that he devised after dissecting the genitalia of museum specimens.

Subject:  Bristle Fly
Geographic location of the bug:  Oakdale NSW
Date: 02/02/2020
Time: 06:58 PM EDT
Your letter to the bugman:  Can you please confirm if the attached image is of a Bristle fly. The markings are slightly different than those on your website.
How you want your letter signed:  Bristle fly?

Tachinid Fly

This is a Tachinid Fly in the family Tachinidae, and some species are known as Bristle Flies because of the course hairs that cover the abdomen of many species.  We believe your individual might be Formosia speciosa which is pictured on Brisbane Insects.