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Entomology (Study of Bugs)/Unknown tropical glowing insect


Glowing insect 2
Glowing insect 2  
Glowing insect 1
Glowing insect 1  
QUESTION: Greetings Ed Saugstad,
  My name is Ed and I live in Puerto Rico. On April 24th, 2013 I stumbled on this insect on the outside of my backdoor (see attachment photos). Though it was too dark to see anything this insect was easily spotted due to it's very distinctive green dots of light coming from both the right and left side of his upper body backside. I will let him free after I finish this message. Any help on identifying this insect will be greatly appreciated by me. Have a great day.

ANSWER: Dear Ed from Puerto Rico - What you have here is a click beetle (Coleoptera: Elateridae) in the genus Pyrophorus. It commonly is known as a cucubano, not to be confused with a true firefly (cucullo). Its larva, which is predaceous on other insects, also has luminous organs. See for a very detailed article (in Spanish) on this insect.
Hope this helps,

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

QUESTION: Greetings Ed,
  Thank you very much for your quick response on my previous question. There is another flying glowing insect I've seen but it is smaller than the one you ID'ed. It also has his one light on his rear end rather than on his back. Though I do not have any photos of it I ask if there is another name for this insect. Have a great day.

Dear Ed - The most likely suspect would be a true firefly (Coleoptera: Lampyridae) - see for an example. Males usually 'flash' while flying slowly above the ground, looking for an answering signal from females waiting there. Some tropical species are noted for flashing in synchrony from perches in trees.

Hope this helps,

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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