Vespa affinis (lesser banded hornet) is a common hornet in tropical and subtropical Asia.
The Lesser banded hornet is a small to medium-sized hornet, with queens reaching up to 30mm, males 26mm and workers averaging 22 to 25mm.
The head is brownish red or black, pubescent, with some red marking on frons and vertex, black temple; compound eyes and ocelli black; dark brown antennae and usually pale brown underneath; black clypeus, coarsely punctate, posterior side of clypeus with broadly rounded lobes; mandibles and tooth black. Thorax black with many punctures and some erected hairs, propodeum black. Legs dark brown. Wings dark fuscous brown, tegulae dark brown. Gaster with some fine punctures, dark brown segments except first and second segment yellowish orange. Some specimens the yellowish orange on the first tergite may be reduced to two transverse spots and narrow apical band.
There are several subspecies or geographical forms. In Hong Kong and South China the wasps are mainly black, with the first two abdominal segments being a deep yellow, forming a conspicuous band. The sides of the head and thorax display some reddish brown. In Southeast Asian regions such as Singapore they are fully black, without reddish brown markings, and the abdominal band is a brilliant orange.