Hundred Pacers are one of the most venomous snakes found in Southeast Asia. The popular name “hundred pacer” refers to a local belief that, after being bitten, the victim will only be able to walk 100 steps before dying. They are also known as sharp-nosed viper, snorkel viper, Chinese moccasin, five-pacer and long-nosed pit viper.
When encountered they may appear sluggish at first, but are very dangerous. They are capable of striking vigorously when threatened. These species are considered very dangerous.
The body of Hundred Pacers are short, thick and slightly flattened horizontally. The head is broad, triangular and distinct from neck. Their neck is thin with nose rapidly tapering to knobbed tip. The top of the head is covered with nine large shields. Their eyes are medium-sized and light brown to brown in colour. Tongue is red with diffused gray. The tail is short, ending in a compressed, pointed slightly curved cornified scale.
There are 17 to 23 rows of scales, which are strongly keeled and dull. They have light brown or greyish brown back. The top of the head is brown in colour while clear triangular patterns can be seen along the sides. The belly has black spots while the tail is a black-brown colour. The young are much lighter than the adults with essentially the same pattern.
Hundred Pacers are active during the day and night. When disturbed, they raise their head while also making a warning hissing sound and constantly waggling their tail. They have heat-sensing organs called pits on the sides of their head which allow them to detect the location of animals or objects that are nearby with incredible accuracy despite the fact that they have very poor eyesight.
Female Hundred Pacers generally produce 11 to 35 eggs. Hatchlings are lighter and more vividly patterned than the adults, but this darkens considerably with age. They are well-developed when born and can deliver a poisonous bite.
Hundred Pacers are medium-sized snakes. They are usually between 2.6 and 3.3 feet long. They reach a maximum length of 5.2 feet in males and 4.6 feet in females.
The diet of these snakes consists of rats and mice, lizards, birds and frogs.
They are found in Taiwan, southern China, northern Vietnam and possibly Laos. These species inhabit high, forested mountains, but have also been found in low coastal regions. They prefer lower mountain slopes or rocky hills with small valleys.
These snake species have lifespan of about 12 to 16 years.