A small to medium-sized hornet, workers generally 17 to 24mm, queens to 30mm.Mainly black. Head and sides of thorax reddish brown.
This species is generally found in temperate areas such as Japan, Russia and Korea. It is considered rare or uncommon throughout its range. In fact, it has been suggested for attention in the Red Database (vulnerable species) in Japan! Read more about this here (in Japanese).
Vespa dybowskii usually nests in above-ground cavities. The nest envelope is usually tubular-imbricate (envelope comprising of sections which run lengthwise).
One unique aspect in this species is that it is a social parasite of Vespa crabro and sometimes Vespa simillima. The queen of Vespa dybowskii takes over the nest of the initial species, and somehow induces the workers to raise her own brood! See photos of this fascinating aspect here (Japanese text).
This species is said to be strongly defensive.