Miner bee, Andrena sp. (Andrenidae).
A spider wasp (Pompillidae: most likely Aupoplus architectus) carries away a paralyzed spider to entomb in a mud case with her eggs. These wasps frequently chew most of their host's legs off to make them easier to transport and stuff in their egg chambers.
Golden Green-Sweat bee, Augochlorella aurata, in Iowa.