What’s That Costa Rican Moth??? Siga pyronia

Subject: Costa Rica moth no. 1
Location: Arenal area, Costa Rica
February 18, 2014 5:59 am
Came to lights at Arenal Observatory Lodge, about 600 meters elevation, Caribbean slope. I identified about 80 others, but none of the books that I could obtain or websites that I found helped with this one. Pictures taken in December 2013.
Unless you have access to better resources than I could find online, please don’t take a lot of time on this. I looked at all the sites listed on this useful page http://www.aprairiehaven.com/?p=14485, in particular the Dan Janzen and Cameron Prybol cites, which where very useful for identifying most of my other moth pictures.
Signature: Ben Jesup

Unknown Moth
Siga pyronia

Hi again Ben,
Thanks so much for resending this image using our standard form and also for providing additional information.  Its robust body indicates it is a larger moth.  Can you recall the approximate size?  It reminds us of moths in the family Erebidae, which includes the Tiger Moths, Underwing Moths and the Black Witch.  This really is a pretty moth with such subtle coloration.  Perhaps one of our readers will be able to provide an identification.

Yes, it is gorgeous–the most striking of the moths that I wasn’t able to identify.  (I did stumble across another picture of online somewhere, but it was unidentified there as well.)  And yes, it was pretty good sized, I would say at least a three-inch wingspan.  I was thinking it might be in one of the genera not too far from the underwing moths, but there are also so geometrids with a similar shape.  Maybe I should try to contact Dan Janzen or Cameron Prybol and see if they would be willing to take a look at the ones I couldn’t identify.
I’m a bit of a Luddite, but sometime I will try to figure out how to post all of pictures so that others might benefit from all of the work that I did trying to identify them.
Thanks again.

Karl provides an identification:  Siga pyronia
Hi Daniel and Ben:
What a beauty! My initial thought was Geometridae but that didn’t pan out so I had to widen my search. Having no luck at my usual sites, I turned to an old favorite of mine that I have been ignoring recently. The Electronic Biologia Centrali-Americana (EBCA) provides access to a vast wealth of information about the fauna of Central America. The information appeared originally in a series of thick volumes, published in the late 19th and early 20th centuries. It can be a little daunting, but always rewarding. Your moth is Siga pyronia, a Crambid Snout Moth in the Family Crambidae. As far as I can tell the genus has only one other species, the gorgeous Moonlight Queen (Siga liris), which lives in South America. The EBCA provides an illustration (see figure 7) and good description on page 198, in: Lepidoptera-Heterocera. Vol. II (1891-1900) by Herbert Druce. In Ben’s photo, what appear to be grey colored bands are actually almost clear (hyaline) bands that allow the grey background to show through. The BoldSystems website also has a number of good pictures. Regards. Karl

Good morning Karl,
We are thrilled to be able to provide Ben with an identification thanks to your meticulous research.

Excellent!  Never would have guessed that it was a Crambid.  And thanks for the reference to the EBCA, which I hadn’t heard of.  It helped me identify a butterfly from my trip.  I looked through all of the moth plates, but couldn’t easily find any of my other unidentified moths.  I’d be curious to hear what Karl’s “usual sites” are—maybe they would help me identify the others.
Thanks again.

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