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Entomology (Study of Bugs)/Pill/ sow bugs tha tlight up??


I have seen several times now late at night while I am out with my dogs in Up state Pa. dim blueish lights in the grass. I thought I was seeing things untill I managed to actualy see the bug that was making the light. It looked like a Sow bug but flater and had a body that was slightly almond shaped with many sgements and several legs . It was a dark brown or black it moved slowly but still fast enought to escape into the grass. I have seen the light before but now I have seen the bug. It was with several sow bugs near a pile of wood chips.
Any idea whatit is?
Thank you . This was seen on Sept 30 , 2013 at 11:00 PM.


I strongly suspect that what you saw was the larva of a firefly (beetle family Lampyridae) or glowworm (beetle family Phengodidae).  Here's more on each: (fireflies) (glowworms)

I do not believe there are bioluminescent sowbugs or pillbugs, which are actually land crustaceans called isopods.


Entomology (Study of Bugs)

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Eric R. Eaton


I answer insect and spider identification questions ONLY. Attach images if possible. No "what bit me?", "what do I feed this bug in captivity?", or science fair project questions please. NO TECHNICAL QUESTIONS ABOUT INSECT PHYSIOLOGY.


Principal author, Kaufman Field Guide to Insects of North America. Professional entomologist employed previously at University of Massachusetts, Chase Studio, Inc., and Cincinnati Zoo; contract work for West Virginia Department of Natural Resources, Smithsonian Institution, and Portland (Oregon) State University.

Author, Kaufman Field Guide to Insects of North America, Missouri Conservationist magazine, Ranger Rick, Birds & Blooms, Timeline (journal of the Ohio Historical Society). I have contributed to several books as well.

Oregon State University, undergraduate major in entomology, did not receive degree.

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One of the top 50 experts in all categories for, 2009.

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Principal author of the Kaufman Field Guide to Insects of North America, Smithsonian Institution (contract), Cincinnati Zoo (employer), Portland State University (contract), Chase Studio, Inc (employer), Arkansas Museum of Discovery (guest speaker). Currently seeking speaking engagements, leadership roles at nature festivals, workshops, and ecotours.

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