Protobothrops kaulbacki, commonly known as the Kaulback's lance-headed pitviper[3] or Kaulback's lance-headed pit viper,[1][4] is a venomous pit viper species endemic to Asia. No subspecies are currently recognized.[3][5]
The specific name, kaulbacki, is in honor of British explorer Ronald Kaulback.[3][6][7][8]
Adult males of P. kaulbacki may attain a total length of 134 cm (53 in), which includes a tail 22.5 cm (8.9 in) long. Females may grow longer: maximum total length 141 cm (56 in), tail 23 cm (9.1 in). Dorsally, it is green, with a vertebral series of dark angular spots, which may be joined to form a zigzag stripe. The top of the head is black with yellow stripes. Ventrally, except for the whitish throat area, it is gray with large squarish or crescent-shaped yellow spots.[9] Scalation includes 25 rows of dorsal scales at midbody, 201–212 ventral scales, 66–78 subcaudal scales, and 8 supralabial scales of which the third is the largest.[4]
Protobothrops kaulbacki had originally been known only from the type locality, which is "Pangnamdim, north of the Triangle, Upper Burma" (Myanmar).[2] In 2005 it was reported also from Tibet (China).[1][10] It also occurs in Arunachal Pradesh (NE India).[3]
Protobothrops kaulbacki is oviparous. The adult female lays a clutch of 6–32 eggs in a hole in the ground, and then remains with the eggs to guard them. Eggs measure 48–53 mm x 26–27 mm (about 2 in x 1 in). Each hatchling is 26–27 cm (about 10½ inches) in total length.[9]
Protobothrops kaulbacki, commonly known as the Kaulback's lance-headed pitviper or Kaulback's lance-headed pit viper, is a venomous pit viper species endemic to Asia. No subspecies are currently recognized.