Gloydius blomhoffii, commonly known as the mamushi, Japanese moccasin, Japanese pit viper, or Japanese mamushi, is a venomous pitviper species found in China, Japan, and Korea. There are four subspecies including the nominate subspecies described here.This species and the Okinawan habu are the most venomous snakes in Japan. Every year, 2000–3000 people in Japan are bitten by a mamushi. Bitten victims typically require one week of treatment in a hospital.