Gloydius – Asian ground pit vipers

A fascinating group of venomous snakes found across much of Asia, from Russia and China down to Korea, Japan, and the northern parts of Southeast Asia. What sets the Asian ground pit vipers apart from many other vipers is their ability to thrive in colder, more northern climates, including mountainous regions and temperate zones where most snake species would struggle. This makes them unusual among vipers, which are often thought of as tropical or desert specialists. Their stocky bodies, broad triangular heads, and heat-sensing pits between the eyes and nostrils give them the classic viper look, but they are smaller and more compact than some of their larger, flashier relatives.

One of the most distinctive features of Asian ground pit vipers is their coloration and patterning. They usually wear a mix of earthy browns, grays, or reddish tones with darker crossbands or blotches along the back, which help them blend perfectly into leaf litter, rocky slopes, or forest floors. They also prefer to lie in wait, striking quickly when prey comes within range, unlike fast-moving whip snakes or racers. Their venom, while not usually as potent as larger vipers, is effective enough to subdue their typical prey, including small mammals, amphibians, lizards, and birds. Because of their smaller size and less aggressive nature, they are often overlooked compared to the more infamous vipers of Asia.

The genus includes several well-known species, such as the Mongolian pit viper (Gloydius halys), also known as the Siberian pit viper, which has one of the widest ranges of any pit viper in the world, from Eastern Europe to China. The Korean pit viper (Gloydius ussuriensis) is another notable member, living in Korea and northeastern China, while Gloydius blomhoffii, the Japanese mamushi, is perhaps the most famous. The mamushi is notorious in Japan as one of the country’s most dangerous snakes due to its wide distribution and frequent encounters with people.