Jerdon’s Lancehead Viper

“On my first trip to western Guizhou, my biggest target was the famous White-headed Viper (Azemiops kharini). On my first night, I found a male Protobothrops jerdonii in the Azemiops area. After realizing they existed in this place, I went on a daytime hike the next morning and found this pictured female. Once I had both genders of this species, I immediately noticed some “weird things” about this population.

This particular locality of Protobothrops jerdonii lives in a totally different habitat from other members of the species. Usually, Protobothrops jerdonii are found in montane cloud forests, while these individuals are found in alpine meadows at high elevations on limestone karst in the western Guizhou Plateau. The scenery of their habitat was breathtaking.

What makes them even more unique among this species is their body shape. All individuals I’ve found in this locality have the stout body shape of terrestrial vipers (similar to most Crotalus and Gloydius species), while most Protobothrops jerdonii are very slender, like other Protobothrops species. I assume this difference relates to their distinct lifestyle and habitat.

Another fascinating feature I’ve noticed in this population—one that doesn’t exist in others—is the drastic sexual dimorphism. Typically, Protobothrops jerdonii show only a slight but noticeable difference between males and females, with females tending to be larger. However, in this particular population, males are larger than females and show significant color differences as adults. The males turn predominantly greenish-yellow with black markings, while the females become mostly black with bright yellow speckles.

This is very intriguing to me. My theory is that the females need to be super dark to absorb enough heat during gestation (unlike other egg-laying Protobothrops, P. jerdonii are viviparous). That’s exactly how I found her—out basking on a sunny morning after a cold, rainy night—and she was clearly gravid.” — Tingkun Luo