Lipotriches ceratina

A male sleeping. Taken at night in Singapore.

Quote from en.wikipedia.org/wiki/Halictid…
The Halictidae is the second largest family of Apoidea bees.[1] Halictid species occur all over the world[2] and are usually dark-colored and often metallic in appearance. Several species are all or partly green and a few are red; a number of them have yellow markings, especially the males, which commonly possess yellow faces, a pattern widespread among the various families of bees.

They are commonly referred to as "sweat bees" (especially the smaller species), as they are often attracted to perspiration.[3] They are likely to sting only if disturbed; the sting is minor.

Most halictids nest in the ground, though a few nest in wood, and they mass-provision their young (a mass of pollen and nectar is formed inside a waterproof cell, an egg laid upon it, and the cell sealed off, so the larva is given all of its food at one time, as opposed to "progressive provisioning", where a larva is fed repeatedly as it grows, as in honey bees). All species are pollen feeders and may be important pollinators.