''Trimeresurus septentrionalis'', commonly known as the Nepal pit viper or northern white-lipped pit viper,Gumprecht A, Tillack F, Orlov NL,

Captain A Captain is a title, an appellative for the commanding officer of a military unit; the supreme leader or highest rank officer of a navy ship, merchant ship, aeroplane, spacecraft, or other vessel; or the commander of a port, fire or police depa ...

, Ryabov S. 2004. ''Asian Pitvipers''. GeitjeBooks. Berlin. 1st Edition. 368 pp. . is a

venomous Venom or zootoxin is a type of toxin produced by an animal that is actively delivered through a wound by means of a bite, sting, or similar action. The toxin is delivered through a specially evolved ''venom apparatus'', such as fangs or a sti ...

pit viper The Crotalinae, commonly known as pit vipers,Mehrtens JM (1987). ''Living Snakes of the World in Color''. New York: Sterling Publishers. 480 pp. . or pit adders, are a subfamily (biology), subfamily of Viperidae, vipers found in Asia and the ...

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

found in

Bangladesh Bangladesh, officially the People's Republic of Bangladesh, is a country in South Asia. It is the List of countries and dependencies by population, eighth-most populous country in the world and among the List of countries and dependencies by ...

Bhutan Bhutan, officially the Kingdom of Bhutan, is a landlocked country in South Asia, in the Eastern Himalayas between China to the north and northwest and India to the south and southeast. With a population of over 727,145 and a territory of , ...

Nepal Nepal, officially the Federal Democratic Republic of Nepal, is a landlocked country in South Asia. It is mainly situated in the Himalayas, but also includes parts of the Indo-Gangetic Plain. It borders the Tibet Autonomous Region of China Ch ...

and

India India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since ...

Description

Total length males 610 mm, females 730 mm. The head scalation consists of 10–11(12)

upper labials In reptiles, the supralabial scales, also called upper-labials, are those scales that border the mouth opening along the upper jaw. They do not include the median scaleWright AH, Wright AA. 1957. Handbook of Snakes. Comstock Publishing Associates ( ...

, the first of which are fused to the nasal. The head scales are small, subequal and feebly imbricate, smooth or weakly keeled. The

supraoculars In scaled reptiles, supraocular scales are (enlarged) scales on the crown immediately above the eye.Mallow D, Ludwig D, Nilson G. 2003. True Vipers: Natural History and Toxinology of Old World Vipers. Malabar, Florida: Krieger Publishing Company. ...

are narrow and undivided with 9–11 interocular scales between them. The temporal scales are smooth. Midbody there are 21 longitudinal dorsal scale rows. There are 162–172 ventrals in males, 160–181 in females. The subcaudals are paired and number 68–83 in males, 55–71 in females. The

hemipenes A hemipenis (: hemipenes) is one of a pair of intromittent organs of male squamates (snakes and lizards). Hemipenes are usually held inverted within the body, and are everted for reproduction via erectile tissue, much like that in the human peni ...

are without spines. The colour pattern is green above. The belly is green, yellowish or white below. A faint ventrolateral stripe present in all males, but absent in females. The end of tail not mottled brown. Holotype: MHNG 1404.31

Geographic range

It is found in Bangladesh, Bhutan, Nepal and northwestern India (

Simla Shimla, also known as Simla (List of renamed Indian cities and states#Himachal Pradesh, the official name until 1972), is the capital and the largest city of the northern Indian state of Himachal Pradesh. In 1864, Shimla was declared the summe ...

). The type locality is given as "Nepal 83^o 55' 28^o 15' 1500 m (Nähe Pokhara)". Regenass & Kramer (1981) list the type locality as "Hyangcha (Nepal) 83^o 55' E.L. 28^o 15' N.B. 1500 m". Holotype: MHNG 1404.31.

Taxonomy

Elevated to a

, ''T. septentrionalis'', by Giannasi et al. (2001). Returned to a subspecies, ''T. a. septentrionalis'', by Leviton et al. (2003). Elevated to a species in another

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

, ''Cryptelytrops septentrionalis'', by Malhotra & Thorpe (2004). Returned to genus ''Trimeresurus'' and placed in

subgenus In biology, a subgenus ( subgenera) is a taxonomic rank directly below genus. In the International Code of Zoological Nomenclature, a subgeneric name can be used independently or included in a species name, in parentheses, placed between the ge ...

''Trimeresurus (Trimeresurus)'' by David et al. (2011). (See synonyms.)

Description

Geographic range

Taxonomy

References

Further reading