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Name: Dennis
Status: student
Grade: K-3
Location: MN
Country: USA
Date: Summer 2012

I am writing you today because myself and my father found some caterpillars tonight that my father said he's never seen before in all his life. The reason is the possible rareness of these 'Glow in the Dark' caterpillars which I have never heard of and my father neither, although he did say he had heard of lightning bugs our aka fireflies. So, we just figured we'd see what the deal is with these unbelievable caterpillars and were hoping to maybe find out what they are because google didn't have anything.


Another name for glowing caterpillars are glow worms.

I found this after googling “glos worms”

I googled “glowing caterpillars” and found

This Youtube movie about glowing caterpillars.

This last search also presented articles on

Why parasites make caterpillars glow:

and others

Happy hunting. Sincere regards, Mike Stewart

Infection with glow in the dark bacteria (transmitted by nematodes - small worm like organisms) kills caterpillars and causes them to glow. This "bioluminescence" makes the caterpillars stand out to potential predators - a built in way to spread the nematodes and the bacteria they carry.

It is also possible that you came across a beetle in the family Phengodidae. The larvae are very caterpillar-like in form and bioluminesce brightly.

Dr. Tim Durham Undergraduate Studies & University Colloquium Department of Biological Sciences Florida Gulf Coast University

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