Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
Photo#204645
Gall - Thecabius populimonilis

Gall - Thecabius populimonilis
Puyallup, Pierce County, Washington, USA
July 21, 2008

Images of this individual: tag all
Gall - Thecabius populimonilis Gall bug - Thecabius populimonilis Gall bug host plant - Thecabius populimonilis

Moved
Moved from Pemphigini.

 
Thank you
Thanks you!

Moved

Moved

Moved
Moved from Galls (see note on second image).

Do you have
this book? I was flipping through it (I'm pretty sure it was this one, unless there's another new guide to insects of the Pacific Northwest) last week when I was in your neck of the woods, and I think it had willow leaf galls similar to the two types you've posted.

 
no
thanks for the link. I'll be getting it now.+

 
Now that I look at this again,
I think the host is some kind of poplar, not a willow--which is reassuring, because all the leaf galls on willows that look anything like this are made by sawflies, from what I can tell. There are several types of aphid galls on poplar leaves, though none of the ones in Felt matches perfectly. That does seem to be an aphid in there--certainly not a sawfly, wasp, midge, or mite.

 
Balsam Poplar
Balsam poplar (Populus balsamifera) has leaves that look like elongated aspen leaves.

 
I don't know
I looked at my tree guide for the area. P. balsamifera ssp. trichocarpa or Black Cottonwood has heart-shaped leaves. The leaves above don't have the heart shape where it connects to the stem. There is also another ssp. P. balsamifera tremuloides, that has flat leaf stalks. It doesn't really look like that either.

 
Variability of specimens and sources
Hi Lynette, I agree that the leaves in your photos do not have a cordate base or a flattened petiole (i.e. they are rounded and terete (round), respectively), but that is consistent with balsam poplar according to several references, including photos in the PLANTS database (hyperlink above) and on the Burke Museum webpage. The description on the Burke Museum page says that the leaves of P.b. ssp. trichocarpa are "usually rounded or truncate at the base,...petioles terete." On its page for the trichocarpa subspecies, the PLANTS photo gallery shows some specimens with a cordate base and others without. Variability among specimens and some variance among references may account for the discrepancy.

 
You're right
It does match those images. I'm convinced it's at least that species.