The Japanese giant hornet (formerly known as Vespa mandarinia japonica) is a color form of the world's largest hornet, the Asian giant hornet (V. mandarinia); though formerly considered a subspecies, it has been treated as a synonym of the subspecies V. m. mandarinia since 1997. It is a large insect, with adults frequently growing to greater than 4 centimetres (1. 6 in) long, with a wingspan greater than 6 centimetres (2. 4 in). It has a large yellow head with large eyes, and a dark brown thorax with an abdomen banded in brown and yellow. The Japanese giant hornet has three small, simple eyes on the top of the head between the two large compound eyes. As the name implies, it is endemic to the Japanese islands, where it prefers rural areas where it can find trees to nest in. In Japanese it is known as the ōsuzumebachi (オオスズメバチ(大雀蜂、大胡蜂), literally "great sparrow bee").
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