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Monarch Caterpillar under Attack
location:  St. Augusta, Minnesota
August 20, 2012
Hi Daniel.
I’m editting photos now, and just came across something interesting.  This fifth instar monarch caterpillar may be under attack by a fly.
Although the photo isn’t as clear as I’d like, if you look near the caterpillar’s head you can see what appears to be a small fly.  I assume it was attracted to the droppings left from the caterpillar’s overnight binge.  I wish I’d noticed it when I was doing the photo.  This seems to be a smaller species than the one I previously noted (August 14th).
This has been a very difficult year for the monarchs and other butterflies here; many many predators and parasites and now, drought.  The spring was spectacular for bug nuts like me, seeing species not usually seem this far north and large numbers of monarchs on our milkweeds.  But it quickly dropped off as we got into the more normal summer season.
Cheers.  And thanks again for your incredible service!
Don J. Dinndorf
St. Augusta (central), Minnesota

Monarch Caterpillar preyed upon by Tachinid Fly

Hi Don,
While we cannot make out details, we can be relatively certain that this Monarch Caterpillar is being preyed upon by a Tachinid Fly, perhaps even the same species of Tachinid Fly from your August 14 submission.  What a marvelous addition to our Food Chain tag despite the sorrow of you losing one on your Monarch Caterpillars to predation, or rather, parasitization.

Thanks, Daniel.  Next time, maybe I’ll get a clearer shot.
The flies have just been murder here.  I lost four metamorphosing caterpillars just today.

What's That Bug? does not endorse extermination

Subject: Looked like a HUGE Wasp but is a Mosquito?
Location: Aberdeen, NJ (Central NJ)
August 20, 2012 7:59 am
I was at a local shop (in Aberdeen, NJ) with my daughter yesterday and happened to see this HUGE flying insect outside the window. I could have sworn this was the largest Wasp I had ever seen but it really appears to be a Mosquito?
Can you please help me out by telling me what this is?
I don’t know what it is but I’m calling it a descendant of Mothra. (Somebody call Godzilla!!!) I would HATE to have that thing bite me!
Signature: Fred from NJ

Hanging Thief

Hi Fred,
This Hanging Thief is a Robber Fly in the genus
Diogmites.  You were astute to notice the similarities between the Hanging Thief and a mosquito because both Robber Flies and Mosquitoes are in the same insect order, Diptera.  Hanging Thieves are formidable predators that often prey upon wasps and bees that they catch on the wing.

What's That Bug? does not endorse extermination

Subject: Thank you
Location: Vancouver Island, BC, Canada
August 15, 2012 3:46 pm
Hi to everyone at WTB,
I found out about your site recently, and I was deeply impressed by the kind and tolerant attitude you promote towards the beings we share the planet with! It’s heartening that in spite of the flak you probably get for the sentiment, you stick by it with such resolve.
Anyway, I thought I’d share a little (literally) bug rescue story that happened here around the end of July. We (my parents and I) are happy to have insects and spiders in our home, the latter having become of special interest since I started learning about spiders with the help of BugGuide. My grandparents feel the same way for the most part, but there are still a few things that irk them! We’d been getting complaints about swarms of tiny flying insects in their kitchen and one of their bathrooms. My mom even reported some tried to boldly go where few flies had gone before: up the noses of her and her co-workers as they ate during a meeting being held there! Needless to say, I got pretty curious after that.
It turned out that food was often left out longer than it should have been, which provided a fine environment for the 2.5mm fruit flies. There were lots, maybe more than a hundred, especially in the kitchen! I was saddened when I learned my grandparents had been killing them, so I offered to transport the bunch to our compost, where fruit flies thrive and are in turn valuable food for wasps, spiders, and other visitors.
I setup some containers which I baited with cherries and grapes, and I also put some fruit on the counter. I wanted to photograph the flies to show my grandparents what amazing creatures they are up close. I then left, and returned an hour later to find dozens of flies taking the bait. I quickly covered the containers, brought them to our compost, and released everyone. Within just a few such trips, most of the flies were gone, and I’m sure much happier in their new home.
The included photograph is of one of the flies feeding on a grape I left on the counter. Unfortunately I didn’t get a chance to shoot any of them from multiple angles. They came and went too fast. I believe they’re in the family Drosophilidae, but beyond that I don’t know. I’ve also posted a shot of a different individual to BugGuide here:
In closing, I should say that while I hope you enjoy the photograph and the story behind it, I’m not asking for an ID on the fly. I know you folks are very busy and don’t want to put any more on your plate. But it’s not everyday that one finds people that genuinely care about ”bugs”, so I wanted to make contact and thank you for running this site the way you do!
Signature: Kyron

Vinegar Fly

Hi Kyron,
This is one of the best letters we have received in quite some time, not only for the sentiment, but also for the depth of the detail that you went into for your explanation.   We also have Fruit Flies, or better Vinegar Flies in our kitchen.  They flock to the overripe bananas and to the garden fresh tomatoes that begin to turn before we have a chance to eat them.  They were tolerated until they discovered the vinegar culture we have been propagating, prompting us to cover the vinegar vat with a layer of thin cloth to keep the buggers out.  We believe your fly is in the genus
Drosophila as it seems to match this image on BugGuide.  We don’t bother to relocate the Vinegar Flies.  We just eliminate the food source and they soon disperse or become prey to the spiders and other predators that are welcome in our home and office.  We do admit that there is a teeming population in our own compost pile and that the lizards are frequently found in the compost pile feeding on the flies that are attracted.  Thank you again for your support and we are tagging this posting with the Bug Humanitarian Award.  In closing, we want to compliment you on the excellent quality of your macro-photograph that is wonderfully detailed and puts our own attempts at macro-photography (we really need a better lens) to shame.

Kyron Responds
Great to hear from you, and thanks for finding the genus.  The fly sure
looks like the one you linked to.  I never knew they liked vinegar or
were called Vinegar Flies.  Very interesting!
We used to have some of these (or related I guess) in our kitchen too,
and we also let them be since their numbers never got very high.
They’ve since disappeared, except for the odd few that occasionally
follow us back from the compost.
I’m very glad you liked the shot and appreciate the compliment.  No
fancy equipment is needed though!  I used the kit (not a macro) lens
that came with my camera, mounted in reverse, as I do for most of my
bug shots nowadays.  One can get some high magnification with very
little expense by reversing lenses.

What's That Bug? does not endorse extermination

Hello again, Daniel.
Apologies for two messages in one day, but our earlier correspondence reminded me of something.  Back on June 25th I sent you a couple of photos of a questionmark  caterpillar that I’d mentioned had later been parasitized by a tachinid fly, which was also raising havoc with my monarch caterpillars.  In answer to your request, I had to say I hadn’t photographed the fly.
Anyway, since then, I’ve kept several of the little maggoty buggers in a medicine bottle, allowed a few to emerge, and then put them in the freezer.  I remembered today, after another monarch was killed.  Here’s a mug shot.  The “pills” are their pupal cases.  I don’t know the species, and I don’t care!
Like so many of these flies, they emerge when the caterpillar is in the process of going into it’s pupal stage, or sometimes even after the chysalis is formed.  Then the maggot comes out, and rappels to the ground on a long filament, and upon finding a spot to it’s liking, becomes a pupa itself.
I understand these amazing creatures role in the natural world.  I’ve read alot about their incredible lifecycle.  But I love moths and butterflies more, and these little monsters seem to take perverse pleasure in killing my favorites right at their peak, after they’ve gone through their entire laval stage.  I hate them!
Anyway . . .
Cheers, and thanks very much for all you do.
Don J. Dinndorf
St. Augusta (central), Minnesota

Tachinid Flies and Pupae

Hi Don,
Thank you for providing such an educational posting on the life cycle of Tachinid Flies for our readership.

What's That Bug? does not endorse extermination

Subject: Wasp?
Location: Northern Virginia
August 13, 2012 7:58 pm
Hello! I found this nasty guy in my house the other day trying to fly through a window. Luckily I found it before my children saw it. I did some searching but couldn’t find anything like it. Is it some sort of wasp? Thanks!
Signature: C.A.

Probably Hanging Thief

Dear C.A.,
This is some species of Robber Fly and we believe it is a Hanging Thief in the genus
Diogmites, however we are unable to find an exact match on BugGuide.  We believe this is closest to the New York Bee Killer, Diogmites basalis, which BugGuide describes as:  “A large reddish brown species, with golden spots on each side of the abdominal segments,” however your specimen appears to lack the golden spots.  Perhaps it is the angle of view.

What's That Bug? does not endorse extermination

Subject: need help identification,
Location: Saugus, California,
August 12, 2012 6:34 pm
Dear ______,
I found this weird insect on the kitchen cabinet today, It looked like a bee but also look like a fly. It is about half an inch long and about a size of a bee. It had the yellow and black stripes on it like a bee, but doesn’t have that one fuzzy abdomen or fuzz at all like a honey bee or a bumble bee. It also had no antennas, but what really got me is the eyes were on top of its head close together like they were touching, and they were big and round like balls, but they had tons of small yellow stripes.
I wasn’t sure if I should look under bee or fly for identifying it,
Unfortunately it got away so I couldn’t get a picture but I used photoshop and drew the best i can of it.
Please respond if you can,
Signature: kelsey

Eristalinus taeniops, we believe

Hi kelsey,
We love your drawing.  We believe that based on your interpretive drawing, your excellent description and your location that you discovered a Flower Fly or Hover Fly in the family Syrphidae, a family that includes many member that mimic bees and wasps.  Furthermore, we are quite confident that it is
Eristalinus taeniops, a species with no common name.  According to BugGuide, it is:  ” A widespread Old World species introduced to California.”

What's That Bug? does not endorse extermination