Therioaphis

Therioaphis Walker

This is a genus of about 30 species that feed on Fabaceae, are related to many tree-feeding aphids, and are in the subfamily Calaphidinae.  None of them are native to North America, I have collected three of them here, and one of them was first discovered in the U.S.A. by me in 2013 (T. tenera in southeastern Idaho). Since moving to Colorado in 2021, I have been able to study T. tenera in the front yard living on “Siberian pea shrub” growing along the road. There is also T. riehmi down the road a stretch and T. trifolii on the volunteer alfalfa in the neighborhood. I should get photos of them all!


Therioaphis trifolii from northern Idaho in April.
Therioaphis sp., probably a fundatrix of T. riehmi from northern Idaho in April.