Protobothrops kaulbacki, commonly known as Kaulback's lance-headed pit viper or Kaulback's lance-headed pit viper,Gumprecht A, Tillack F, Orlov NL, Captain A, Ryabov S (2004). Asian Pit vipers. Berlin: Geitje Books. First Edition. 368 pp. . is a pit viper species endemic to Asia. There are no subspecies that are recognized as being valid.
Etymology The specific name, kaulbacki, is in honor of British explorer Ronald Kaulback.Smith MA (1940).Guo, Peng (2007). "New evidence on the phylogenetic position of the poorly known Asian pitviper Protobothrops kaulbacki (Serpentes: Viperidae: Crotalinae) with a redescription of the species and a revision of the genus Protobothrops ". Herpetological Journal 17 (4): 237–246.Beolens, Bo; Watkins, Michael; Grayson, Michael (2011). The Eponym Dictionary of Reptiles. Baltimore: Johns Hopkins University Press. xiii + 296 pp. . (Protobothrops kaulbacki, p. 138).
Description Adult males of P. kaulbacki may attain a total length of , which includes a tail long. Females may grow longer: maximum total length , tail . 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.Smith MA (1943). The Fauna of British India, Ceylon and Burma, Including the Whole of the Indo-Chinese Sub-region. Reptilia and Amphibia. Vol. III.—Serpentes. London: Secretary of State for India. (Taylor and Francis, printers). xii + 583 pp. (Protobothrops kaulbacki, p. 512). 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.
Geographic range P. kaulbacki had originally been known only from the type locality, which is "Pangnamdim, north of the Triangle, Upper Burma" (Myanmar). In 2005 it was reported also from Tibet (China).Rao D, Zhao E (2005). "A New Record from China – Protobothrops kaulbacki (Reptilia, Serpentes, Viperidae)". Acta Zootaxonomica Sinica 30: 209-211. It also occurs in Arunachal Pradesh (NE India).
Habitat The preferred natural habitats of P. kaulbacki are forest, shrubland, and grassland, at altitudes of .
Reproduction P. 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.
Behavior P. kaulbacki is terrestrial and partly arboreal.Harrington, Sean M.; de Haan, Jordyn M.; Shapiro, Lindsey; Ruane, Sara (2018). "Habits and characteristics of arboreal snakes worldwide: arboreality constrains body size but does not affect lineage diversification". Biological Journal of the Linnean Society 125 (1): 61–71.
References
Further reading Kraus, Fred; Mink, Daniel G.; Brown, Wesley M. (1996). "Crotaline Intergeneric Relationships Based on Mitochondrial DNA Sequence Data". Copeia 1996 (4): 763–773. (Protobothrops kaulbacki, new combination). Smith MA (1940). "The Amphibians and Reptiles obtained by Mr. Ronald Kaulback in Upper Burma". Records of the Indian Museum 42: 465–486. (Protobothrops kaulbacki, new species, p. 485, Plate VIII, Figure 5).