Honey bees are not the only bee species that are significant for human wellbeing. I found this Halictine bee resting by biting and hanging on to seed cluster of grass. Halictine bees which are also known as “sweat bees,” as they are often attracted to perspiration. They play a vital role in the pollination ecology. These flower loving insects surpass all other bees and thus are mainly responsible for conserving a bewildering variety of wild and cultivated flowers pollinated by insects.
The Halictidae consists of very large and nearly cosmopolitan family of the order Hymenoptera. They are small to midsize (4 to 9 mm) bees which are usually dark-coloured 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. When pinched, females can give a minor sting.
The Halictidae are the largest family of short-tongued bees in the Indian Region distributed in almost all the zones. It accounts for about one-third of all the Oriental bee species, and this family is possibly the most abundant as many of its species occur in large numbers. Because of their extensive range of adaptation to different climatic conditions the halictine bees are the major pollinators of wide range of flowering plants. It contains four subfamilies namely Rophitinae, Nomiinae, Halictinae and Nomioidinae all over the world. From India it is represented by all the four subfamilies, 27 genera covering 194 species.
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 are important pollinators.
Many species in the subfamily Halictinae are eusocial at least in part, with fairly well-defined queen and worker castes (though not the same as the caste system in honey bees), and certain manifestations of their social behaviour appear to be facultative in various lineages.
Several genera and species of halictids are cleptoparasites of other bees (mostly other halictids). The most well-known and common are species in the genus Sphecodes, which are somewhat wasp-like in appearance (often shining black with blood-red abdomen, usually 4-9 mm in body length); the female Sphecodes enters the cell with the provision mass, eats the host egg, and lays an egg of her own in its place.
Some Halictidae are found active only at dusk or in the early evening, so are called “vespertine” (e.g. in the subgenus Sphecodogastra of Lasioglossum), or sometimes truly nocturnal (e.g. in the genus Megalopta). These bees, as is typical in such cases, have greatly enlarged ocelli.
Different bee genera pollinate different plant species, although there is some overlap that acts as a buffer as bee populations wax and wane. For healthy ecosystems, including agro-ecosystems both diversity and abundance in the bee fauna is important.