The genus Nomia (family Halictidae) are small bees with colourful stripes on their abdomens. These are among the more frequently seen types of sweat bee in the Asia-Pacific region, and there are many species. Identification is a task for the specialist and requires extremely close examination and possibly dissection of specimens. They are mostly similar in habits and behaviour, so for our purposes exact species identification is not necessary.
They average 9 to 10mm in body length, and are mainly black. The abdomen generally has around three or four thin shiny bands which are various shades of blue, green, orange and metallic golden.
These bees are quite common throughout much of their range, but are difficult to spot due to their small size. Although known as sweat bees, this group do not seem attracted to sweat like their New World (American regions) counterparts are. Or maybe they are, but I have not experienced it myself!
These bees nest underground; they supposedly make tiny burrows at an angle to the soil surface. However, I have never seen a nest of these bees myself.
These bees can be considered absolutely harmless. A sting is mild, like a light pinprick.
Photo copyright and courtesy of Tan Siong-Kiat (Singapore)