unknown larval sac - BugGuide.Net

Bagworm moth (Psychidae)

This would be in the genus Oiketicus, but there is not a species known to occur in AZ that makes a bag like this (large; horizontally placed twigs; covered with silk). Some that are found in southern Mexico look very similar. Knowledge of these moths is very spotty, so it may be one of those.

My comments are based on "Bagworm Moths of the Western Hemisphere," 1964. Although that's decades old, no additional species (other than tiny northern ones) have been documented in the US since then. Neat find, whatever it is!

Was it really around 6 inches though? 4 inches is about the biggest one I've ever heard of, I think.

… Charley Eiseman, 18 March, 2009 - 9:38pm

Bagworm moth (Psychidae)

Charley,

Thank you very much for the information. The bag very well may have been closer to 4 inches. I wish now that I had measured it in the field, given the apparent significance of size. I am continually reminded of the potential for new and unusual bugs in southern Arizona. Whatever it is, you are certainly welcome to use the photo in your proposed book if you so desire.

Thanks again,
Ken

… Ken Kertell, 23 March, 2009 - 7:12pm

Glad to help

--and thanks for the offer. I'm using a photo from Florida of O. abbotii, which is comparable but without the layer of silk on the outside.

It would definitely be worth collecting some of these to see what emerges, if you find them again. Only males actually emerge as winged adults--the females are wingless and just lay their eggs inside and die there. So if you collect a female bag, what emerges is a bunch of larvae carrying their own tiny versions of this bag.

… Charley Eiseman, 23 March, 2009 - 7:46pm