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Entomology (Study of Bugs)/Biggest maggot in the world?



I'd like to know what is the largest maggot/fly larva in the world? Please donīt send any photos, though, cause I actually have a phobia of them (that's why I havenīt googled for it), but you know what they say, what scares us also tends to fascinate us. Truth is I am interested on all animals but I know very little about maggots/flies because my phobia prevents me from searching info on them...


ANSWER: Dear J - This is a very difficult question to answer, as the larvae (maggots) of many fly species are poorly known or even undescribed. For example, the larval stages of largest known fly, Gauromydas heros (Diptera: Mydidae), are completely unknown. But as the adult fly can be up to 6 cm long (about 2.3" - see, I would expect that its larva could easily reach 8 cm or more. Based on the morphology of the larvae of smaller mydas flies, I would expect that it would be the largest based on weight as well. The larvae of some flies in the family Syrphidae (ones known as rat-tailed maggots) can reach 7 cm in length, but more than 5 cm of that is just a very thin breathing tube, so the actual body wouldn't weigh much. Personally, the largest fly larva I've seen was that of a horse fly, and it was about 1.5" long.
Hope this helps,

---------- FOLLOW-UP ----------

QUESTION: Hi, thanks for ur answer! :> Very interesting. What sort of lifestyle would be expected for the Gauromydas heros larvae? I'm guessing they live underground or something as they are still unknown?

Also, what do you know about a maggot known as the African tumbu fly? (I think that was its name).

Dear J - Based on what is known about the habits of other species in that family, I would guess that the larvae of Gauromydas heros would be found in leaf litter/moist forest soil or rotting wood where they would prey on other insects (primarily larvae) found in that habitat. As for the tumbu fly (Cordylobia anthropophaga; Diptera: Calliphoridae), they develop beneath the skin of mammals, including dogs and humans. The medical term is for this is cutaneous myiasis. You can find detailed information at - don't worry, the article does not include any gross images.

Hope this helps,

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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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