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Entomology (Study of Bugs)/Mystery mouse parasite.


The King wrote at 2011-07-14 07:32:56
I literally just found a dead mouse in my boiler room. A black mass was sticking out the back end so i touched it with a wire and it crawled out. the exact same thing.

Kel wrote at 2012-03-31 19:14:05
We have 2 cats one of which loves to hunt any type of creature it can carry in his mouth from snakes to rats and beetles, he came up to the back porch with a small rat in mouth and played vigorously til it was dead, I watched in awe and seen what at first I thought was poop til it completely came out and saw what Doug had a picture of, just wanted to find out if that was common as well as attaching to body

Cyan wrote at 2012-08-29 02:37:39
My cat caught a field mouse today and I got him to drop it.  I watched a grub just like this emerge from what I would swear was the mouse's rectum.  At first I thought the mouse was oozing feces from the trauma caused by the cat.  Amazing.

T.L. wrote at 2013-08-13 07:49:06
That is an excellent photo.  I have caught a mouse in a live trap.  A bot fly larvae was attached to the rear of the mouse.  At first I thought the mouse was loosing its uterus or something because the object attached to the mouse was moving.  It then detached itself from the mouse and was worming around inside the live trap.  I tried to take photos but because I didn't want the mouse to escape I couldn't get a good photo.  I was creeped out by this parasite thinking it was some sort of Alien species......only to find out it is a bot fly larvae!  The mouse didn't seem to mind the larvae attached to it and didn't seem to notice when it became detached.  

Thanks. Tara

Entomology (Study of Bugs)

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Ed Saugstad


Will accept most questions in general entomology, including those related to medical entomology, taxonomy, ecology, arthropod surveillance, and pest management. If you are requesting a 'mystery bug' identification, PLEASE either attach an image to your question, or post an image on a web page (such as Flickr) so that I can look at it, as verbal descriptions frequently are insufficient for a definitive identification.


21 years in the U.S. Army as a medical entomologist; duties varied from surveillance of pest populations (including mosquitoes, cockroaches, ticks, and stored products pests) to conducting research on mosquito-virus ecological relationships and mosquito faunal studies. Ten years as a civilian analyst for the Department of Defense, primarily on distribution of vector-borne diseases worldwide. Limited experience on surveillance of agricultural insects in North Dakota and Indiana.

Entomological Society of America, West Virginia Entomological Society, Society for Vector Ecology, National Speleological Society, West Virginia Association for Cave Studies.

American Journal of Public Health, Contributions of the American Entomological Institute, Japanese Journal of Sanitary Zoology, Journal of Economic Entomology, Mosquito News, and Mosquito Systematics.

B.S. in entomology from North Dakota State University in 1963, M.S. in entomology from Purdue University in 1967.

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