The Japanese hornet, formally known as Vespa mandarinia, is widely recognized by its common name, the “Giant Asian Hornet.” Its imposing physical dimensions often spark curiosity and prompt questions about its appearance and natural habitat.
Its True Size
The Japanese hornet is the largest hornet species globally. A queen’s body length can exceed 5 centimeters (2 inches), reaching up to 5.5 cm. Worker hornets are slightly smaller, typically measuring between 3.5 to 3.9 centimeters (1.38 to 1.5 inches) in body length. This makes them significantly larger than most other hornet and wasp species.
Beyond its body length, the Japanese hornet possesses an impressive wingspan. Its wings can extend up to 7.6 centimeters (3 inches). This expansive wingspan contributes to its powerful flight capabilities, allowing it to cover considerable distances.
Visual Identification Beyond Size
While its size is a defining characteristic, the Japanese hornet displays other physical features. Its head is a prominent light orange or yellow, with brown antennae that have a yellow-orange base. The hornet’s eyes are dark brown to black and relatively small compared to its broad head.
The thorax is dark brown or black. Its abdomen is striped with alternating bands of dark brown or black and a yellow-orange color, consistent with its head. The sixth abdominal segment is typically yellow. It possesses large, powerful orange mandibles, which include a black tooth used for digging.
Comparing Its Scale
Comparisons with more common insects can be helpful. A typical honeybee, for instance, is considerably smaller, with the Japanese hornet being roughly four times its size. The Japanese hornet’s wingspan alone can be three times that of a honeybee. This size disparity makes the hornet a formidable predator for honeybee colonies.
The European hornet (Vespa crabro) is another species often mistaken for the Japanese hornet, but it is noticeably smaller. European hornets typically measure between 2.5 and 3.5 centimeters (1 to 1.4 inches) in length. Even eastern cicada killers, which can be up to two inches long, have different abdomen patterns and head proportions. The Japanese hornet’s size can be likened to that of a human thumb.
Where It Is Found
The Japanese hornet is native to temperate and tropical regions across East Asia, including Japan, China, Korea, and parts of the Russian Far East. It is particularly common in rural areas of Japan.
These hornets prefer habitats in low mountains and forests, generally avoiding open plains and high-altitude areas. They establish their nests primarily underground, often utilizing pre-existing cavities like tunnels dug by rodents or spaces near rotten pine roots. Aerial nests are extremely rare in their native Japanese range.