These are images of a green Sweat Bee, with skinny hind legs that I believe is a male Honey-bellied Agapostemon, Agapostemon melliventris.
Full Size Image: Click Here
ID Info:
Keying to species of Agapostemon: (Roberts 1972) Here is a link to the key (listed on the genus page): Revision of the Bee Genus Agapostemon (Hymenoptera: Halactidae)
KEY TO SPECIES OF THE UNITED STATES AND CANADA:
1. - antennae with 11 flagellomeres, no scopa on hind legs (male) = 14
14. - clypeus normal, little broader than long = 15
15. - first metasomal tergum yellow to very pale amber basally, not brown or black, and hind basitarsus always slender and simple; hind legs yellow with small brown or black area apically on femur and basally on tibia = melliventris Cresson, (1874)

Additional ID Info From DiscoverLife.org:
Males of A. melliventris may be distinguished from males of other species found in the Northwest by the restriction of brown or black to narrow subapical bands on its metasomal terga. = pass

Testing for any look-alike possibilities in this geographic area:
(Additional visible qualities) mid legs all yellow, hind legs thin and hind tibia without a black spot on posterior, antennae base with light color on both dorsal and ventral sides:
A. angelicus = fail
A. femoratus = fail
A. melliventris = pass
A. obliquus = fail
A. texanus = fail
A. tyleri = fail
A. virescens = fail