Entomology (Study of Bugs)/Moth Identification


Moth on wall
Moth on wall  
I hope you had a good vacation. Can you tell me what I have here?

This moth was photographed in Sierra Vista, AZ (10 miles north of the international border in the southeastern corner of the state) at 11:15am on July 26, 2012 at an elevation of 4,625' near the eastern base of the Huachuca Mountains in the San Pedro River Valley.

The brick height in the photo is 3.5" therefore I make the wingspan to be approximately 130mm and body length 45mm. It appeared to have just laid 3 spherical eggs approximately 1.5mm in diameter.

Thank you in advance for taking the time to share your expertise.


Thank you for sharing the image and information!

The moth is a giant silkmoth known as "Oslar's Eacles," Eacles oslari .  It is related to the eastern U.S. "Imperial Moth."  Here's more:


Coincidentally, a couple weeks ago I was in Arizona for a National Moth Week event.  We had several of these show up at our blacklights.

Enjoy the unique insect fauna, you live in a very rich area :-)


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.

Awards and Honors
One of the top 50 experts in all categories for AllExperts.com, 2009.

Past/Present Clients
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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