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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.
Palm Beach Gardens, Fl.

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.