Metallic Green Native Bee, Augochlora species.
This tiny and very fast-moving, alert bee is hard to photograph. I found it nectaring on Eupatorium serotinum, a/k/a late-flowering boneset, in the West 11th Street Park in the Heights section of Houston, Texas, on September 23, 2007.
Image: Biosparite [larger view].
The Green Metallic Bee in the genus Augochlora, in the Halictid Family. According to the Audubon Guide: the “Female digs nest of many branching burrows in dead wood or uses pre-existing borrows of other insects. Female supplies each cell with pollen ball and nectar, and lays an egg on each ball. Larvae or pupae overwinter. Adults emerge in spring.”