Metallic green bees (Hymenoptera: Halictidae: Agapostemon spp.) are found only the new world, but they range all the way from British Columbia to Argentina. Although there are over 4,000 known species of sweat bees, this particular subgroup contains only about 44 known species. Most are found in the tropical Americas, but about a dozen range into more temperate climates.
Like many bees and wasps these individuals excavate tunnels in the ground to build their nests. Some species are communal and share resources to some extent, but others are completely solitary.
Adults of both sexes feed on pollen and nectar from a wide variety of flowers. Females go out of their way to collect excess pollen in order to provision their subterranean nests. The pollen balls the mothers collect provide enough nourishment for their larvae to grow and develop until they pupate. Once their young emerge as adults, they’re on their own.