Currently viewing the category: "Tachinid Flies"
What's That Bug? does not endorse extermination

Subject:  Fly identification
Geographic location of the bug:  Idaho
Date: 09/15/2017
Time: 11:16 PM EDT
Dear Mr. Bugman,
I took a photo of a large, mostly black fly with two white dots on the rear part of its abdomen. I have only found the fly outside once. All other flies inside my house are plain black with no white dots. I have attempted to find the type of fly online but with no luck so far. If you know what type it is I’d be very interested to hear. Thank you for your time and help!
How you want your letter signed:  Sincerely, Sarah

Tachinid Fly

Dear Sarah,
This is a parasitoid Tachinid Fly, and according to BugGuide, there are  “1350 spp. in >300 genera of 4 subfamilies in our area [North America].”  We quickly scanned BugGuide down to the tribe level and could not locate this particular species.  Tachinid Flies are important biological control agents against other insects and arthropods, and according to BugGuide:  “Larval stages are parasitoids of other arthropods; hosts include members of 11 insect orders, centipedes, spiders, and scorpions. Some tachinids are very host-specific, others parasitize a wide variety of hosts. The most common hosts are caterpillars. Most tachinids deposit their eggs directly on the body of their host, and it is not uncommon to see caterpillars with several tachinid eggs on them. Upon hatching the larva usually burrows into its host and feeds internally. Full-grown larva leaves the host and pupates nearby.”  If time permits, we will try to identify your Tachinid Fly to the species level, but now you also know where to do the research.  If you find a visual match, please let us know.

What's That Bug? does not endorse extermination

Subject: What species of fly is this?
Location: Clinton, Maine
August 18, 2017 1:48 pm
This is a fly my son found in our flower garden. It is summertime here in Maine and I don’t recall ever seeing this fly! We have many living next to a farm, but this little guy is quite exquisite! Can you tell me what he is please?
Signature: Kristy Richard

Tachinid Fly: Belvosia borealis

Dear Kristy,
This is a parasitoid Tachinid Fly, and we are quite confident it is
Belvosia borealis because of its similarity to this BugGuide posting, also from Maine.  According to BugGuide, the larvae feed “on Ceratomia spp. (Sphingidae).”

Tachinid Fly: Belvosia borealis

Tachinid Fly: Belvosia borealis

What's That Bug? does not endorse extermination

Subject: Tersa Sphinx Moth
Location: Apopka, FL
August 16, 2017 1:31 pm
Found this moth on my house, took this picture then noticed something on it that seemed to be eating into it’s side. I destroyed the thing and the moth few up to the ceiling where it is now. My question is what is the thing?
Signature: Jill

Tersa Sphinx with parasite

Dear Jill,
We suspect this might be a Dipteran parasite, perhaps a Tachinid Fly, on this Tersa Sphinx.  It is possible the infestation occurred while this moth was still a caterpillar.  We are currently searching unsuccessfully, for evidence of Tachinid Flies using Sphinx Moths as hosts.  The Moth Photographers Group has a nice parasite page.

What's That Bug? does not endorse extermination

Subject: Orange hairy butt fly
Location: Central NY, south of Ithaca
July 31, 2017 7:53 am
I was intrigued by this fly whilst walking my dog early one morning in late July. It was relatively slow moving and stuck around the same plant for a few minutes. It was the size of a large housefly. I encountered it on a mowed walking path near some grain fields at the edge of state forest land, in the Finger Lakes region of New York State. What is this delightful creature?
Signature: Andrea

Tachinid Fly

Dear Andrea,
This is a parasitoid Tachinid Fly or Bristle Fly, but we are uncertain of the species as there are many similar looking species in this very large family.

What's That Bug? does not endorse extermination

Subject: Mother & babies or mass parasitism?
Location: Altadena CA foothills (chaparral)
June 18, 2017 7:08 pm
We have no idea what’s happening here… I strongly suspect parasitism?? Forwarding the photo to What’s That Bug for consultation!
Signature: Lori & Neighbors in Altadena

Caterpillar and Parasitoid

Dear Lori and Neighbors in Altadena,
This Caterpillar is definitely the victim of a Parasitoid.  Alas, we don’t think we will be able to accurately identify either species.  The Caterpillar appears to be an Inchworm in the family Geometridae, but we would need to see the prolegs to know for certain.  We suspect the parasitoid may be a species of Tachinid Fly.

What's That Bug? does not endorse extermination

Subject: Strange bee faced fly
Location: Nashville, TN
May 11, 2017 12:25 pm
Hello!
My mother and I were sitting on our front porch and noticed this insect flying around. It landed a few times and stayed still for a good length of time each time without moving so I got a few decent pics. It’s furry and black and has what looks like the face of a bee. Every year I feel like I see an insect that I’ve never seen before. This is the one for this year so far:
Signature: Any info would be appreciated, Nora

Tachinid Fly

Dear Nora,
This is some species of Tachinid Fly, and members of its family are all beneficial predators that parasitize a variety of host creatures that helps in population control.  Sometimes a species of Tachinid Fly is the only known predator of a significant agricultural pest species.  This BugGuide image is similar to the image you provided, though we cannot confirm that they are the same genus or species.

What's That Bug? does not endorse extermination