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Rodent Bot Fly Maggot (and it’s edible)

Squirrel insect
These grubs or insects showed up in my cabin along with a dead squirrel the cat brought in. Could be that its a coincidence or perhaps the cat brought them as an additional gift. The insects were not on the squirrel. Can you help me identify these so I can decide weather they a friend or foe.
Rick in Western Colorado

botfly maggots rick Rodent Bot Fly Maggot (and its edible) botfly maggot rick Rodent Bot Fly Maggot (and its edible)

Hi Rick
Here is one sure to gross out our readership. These are Rodent Bot Fly Maggots, Cuterebra species. The Rodent Bot Fly is a mammalian endoparasite. According to a website we located: “The female flies will lay their eggs along rabbit trails and near rodent burrows. The first stage larvae will hatch and quickly attach to hair when a host brushes against the egg. The larvae then burrow into the skin and leave a breathing hole. ” Also on the website is the information: “Cuterebra is a normal bot fly of rodents and rabbits, but can also infect cats, dogs, and man. The adult fly looks like a bumblebee and is rarely seen. It may appear a shiny blue or black color. The third stage larva is dark brown to black with stout black spines. ” Your close-up photo shows the mouth hooks of the maggot, substantiated by this image on BugGuide. Bot Flies are also known as Warble Flies due to the lumps visible on the skin of the hapless host. There is also a Human Bot Fly, Dermatobia hominis, that is found in Central America.

Wolves on Rabbits
(08/15/2007)
Daniel…
After just reading your description of the bot fly larvae, I’m wondering…at certain times of the year (usually late summer, early fall) when my father would go rabbit hunting, (we actually depended on them for food in the ’50′s), they would sometimes get rabbits with what they then called ‘wolves’ in their necks and we were not allowed to use them for a food source. Could it be that I’ve learned after all these years that these were actually bot fly larvae? I large lump would most times be visible. Does this actually damage the meat for human consumption? Thanks for taking the time to read my query and if you have time to answer, that would be great, but if you don’t, I understand…. Sincerely,
Pat, Hawk Point

Hi Pat,
It sounds like your rabbits with wolves were parasitized by a Bot Fly. The meat near the wolf or warble might be unsavory, but cooking the meat would definitely kill the parasite.

Joanne Gets Sick!!!(08/15/2007) The Rodent Bot Fly
Will you pay for cleaning my nice leather recliner cuz I just barfed on it.
Joanne

Close Encounter with a Human Bot Fly!!!
(08/15/2007) Human Bot Fly experience
Hello fellow bug-nuts,
Your recent posting of the rodent bot fly larvae brought back some interesting memories. I brought an unexpected souvenir home from a trip to Costa Rica in ’00. You guessed it. Luckily, I’d read about these critters. Made me the hit of my local doctor’s office. I actually printed a page from a Canadian website and brought it along in to prove I knew what I was talking about. It is a very weird sensation to feel these beasts move when they’re in your flesh (mine was in the flab of my upper left arm). You can actually feel the bristles they anchor themselves with as they twist about. The research I did told me the adult female bots actually wrestle a mosquito down and lay an egg on the mosquito’s abdomen. Then the mosquito bites a host, the egg on her belly hatches (very quickly, apparently), and the newborn enters the mosquito’s bite site. My research also gave me the bot’s larval timeline, so I knew how long I had, and how insistent to be at the doctor’s office. Love your site! I check it every day.
Don J. Dinndorf
St. Augusta, MN

Bot Fly Larvae are Edible
edibility update on bot fly
Hi Daniel,
Just to keep the gross-out fest going, and to answer Pat’s question: I’m pretty sure that NO, the presence of bot fly larvae would not render the host animal inedible. There’s a good deal of documentation [as recent as 1918] of Inuit hunters taking down caribou that were infested with large fly larvae, and then making a point of cooking and eating the larvae first. Not sure if I could do it, especially considering the textural issue of those rough, stubble-like projections all over the larvae’s sides, but the point is that if some people enjoyed eating the actual flesh-consuming maggots, then eating the rest of the animal would not be a big deal. Reluctance to do so is pure ‘fussiness’ on our part. Best,
Dave
www.slshrimp.com

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¶ Posted 15 August 2007 § Maggots ‡ Comments (1) ° Tagged: Edible Insects: Tasty Morsels

Rodent Bot Fly Pupa

What the Hell is This!!!
Please Help!
This is probably one of the sickest stories you’ll come across.. It was like a scene out of “Aliens”. This morning, I came across our pet greyhound, Merlin, calmly sitting in our family room, with what appeared to be a rather large, dead rat in his jaws!!! He immediately dropped it, once I told him to. Our back yard, while fenced in, is bordered by wooded areas. Consequently, we do get the occasional mouse or rat in the yard. The rat, upon further inspection was not dead. It was fairly mangled up and appeared to be taking its last gasps of air. I grabbed a plastic bag and like picking up dog poop, grabbed the rat by the tail and took it out back. My wife, by this time, had joined me and the initial shock of finding such a large, disgusting “present” in the house had slightly abated; we were quite impressed by its size. As I turned the rat around by the tail, I thought I was looking at internal organs that were beginning to “protrude” through the puncture holes and small lacerations on the rat’s body. . . . To my and my wife’s horror, we realized that these were not organs, but large writhing “things” (grubs, worms, maggots)!!!!????, boring their way out of the body. I quickly disposed of the “present”, but not before one of the things in question, dropped to the pool deck, where I scooped it into a plastic bag for identification. . . . Since we have no idea what this thing might be, my wife is now worried that our beloved grey may have swallowed or eaten one of these creatures and that at this very moment, it is making a lovely home for itself and its larvae in the body of our greyhound. Doubtful, but I am passing along the concern. If you can make out the picture, it is segmented and colored a dark- greenish black. Tried to identify it myself, but had no luck. Hope you can help.
MP
Palm Beach Gardens, Fl.

botfly pupa Rodent Bot Fly Pupa

Hi MP,
Based on just your vivid description, we would identify your creature as a Rodent Bot Fly, Cuterebra emasculator. This fly which resembles a Bumble Bee lays its eggs indirectly on habitat and the warmth of the rodent body causes the eggs to hatch and the maggots to attach to the host animal. The maggot then enter the rodents body through an opening, either being licked inside or by boring through the eye membrane. It then settles beneath the skin and forms a warble, a type of pimple through which the parasite can breath and excrete. The parasite is rarely transfered to another host, and the risk to predators is minimal. Just to add to your nightmare, there is also a Human Bot Fly, Dermatobia hominis, reported from Central America. We have not been able to locate a photo of the Bot Fly Pupa, but your image is consistant with fly pupa, and the supporting story lends credance to our identification.