Common names: Pope's tree viper, Pope's bamboo pitviper.

Trimeresurus popeorum is a venomous

Venomous snake

"Poisonous snake" redirects here. For true poisonous snakes, see Rhabdophis.Venomous snakes are snakes which have venom glands and specialized teeth for the injection of venom...

 pitviper

Crotalinae

The Crotalinae, commonly known as "pit vipers" or crotaline snakes, are a subfamily of venomous vipers found in Asia and the Americas. They are distinguished by the presence of a heat-sensing pit organ located between the eye and the nostril on either side of the head...

 species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 found in northern India, Southeast Asia

Southeast Asia

Southeast Asia, South-East Asia, South East Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia. The region lies on the intersection of geological plates, with heavy seismic...

 and parts of Indonesia

Indonesia

Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...

. Three subspecies

Subspecies

Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...

 are currently recognized, including the nominate subspecies described here.

Description

Grows to a total length 770 mm, tail length 170 mm.

Dorsal scales

Dorsal scales

In snakes, the dorsal scales are the longitudinal series of plates that encircle the body, but do not include the ventral scales.When counting dorsal scales, numbers are often given for three points along the body, for example 19:21:17...

 in 21 (rarely 23) longitudinal rows at midbody; 9-11 upper labials, first upper labials separated from nasals by a distinct suture; a single supraocular; above green, below pale green to whitish, the two separated by a bright bicolored orange or brown (below) and white (above) (males) or white (females) ventrolateral stripe, which occupies the whole of the outermost scale row and a portion of the second row; ventrals 155-169; subcaudals 52-76, in males the base of the tail enlarged to the level of subcaudals 20-25; hemipenes long and slender, smooth, without spines.

This species is most often confused with T. s. stejnegeri

Trimeresurus stejnegeri

Trimeresurus stejnegeri is a venomous pitviper species found in India, Nepal, Burma, Thailand, China and Taiwan. Three subspecies are currently recognized, including the nominate subspecies described here.-Description:...

 (q.v.), the two have quite distinct hemipenes, which does not make identification of individuals in the field or in the laboratory any easier without recourse to (a) male individuals and (b) an examination of the hemipenes. However, the two species are not known to have overlapping distributions, at least based on available materials. Also, closely allied to T. popeorum is T. s. yunnanensis

Trimeresurus stejnegeri yunnanensis

Trimeresurus stejnegeri yunnanensis is a venomous pitviper subspecies found in India and Burma.-Description:The scalation includes 19 rows of dorsal scales at midbody, 154-164/150-172 ventral scales in males/females, 61-71/52-65 subcaudal scales in males/females and 9-11 supralabial...

 (q.v.); ordinarily, the two are more easily be told apart by the number of midbody dorsal scale rows, 21 in T. popeorum, 19 in T. s. yunnanensis.

Geographic range

Northern India

India

India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

, Burma, Thailand

Thailand

Thailand , officially the Kingdom of Thailand , formerly known as Siam , is a country located at the centre of the Indochina peninsula and Southeast Asia. It is bordered to the north by Burma and Laos, to the east by Laos and Cambodia, to the south by the Gulf of Thailand and Malaysia, and to the...

, West Malaysia and Vietnam

Vietnam

Vietnam – sometimes spelled Viet Nam , officially the Socialist Republic of Vietnam – is the easternmost country on the Indochina Peninsula in Southeast Asia. It is bordered by China to the north, Laos to the northwest, Cambodia to the southwest, and the South China Sea –...

. In Indonesia

Indonesia

Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...

, it occurs on the islands of Sumatra

Sumatra

Sumatra is an island in western Indonesia, westernmost of the Sunda Islands. It is the largest island entirely in Indonesia , and the sixth largest island in the world at 473,481 km2 with a population of 50,365,538...

, Mentawai Islands

Mentawai Islands

The Mentawai Islands are a chain of about seventy islands and islets off the western coast of Sumatra in Indonesia. Siberut is the largest of the islands. The other major islands are Sipura, North Pagai and South Pagai . The islands lie approximately 150 km off the Sumatran coast, across the...

 (Siberut

Siberut

Siberut is the largest and northernmost of the Mentawai Islands, lying 150 kilometres west of Sumatra in the Indian Ocean. A part of Indonesia, the island is the most important home for the Mentawai people. The western half of the island was set aside as the Siberut National Park in 1993...

, Sipora, North Pagai

North Pagai

North Pagai is one of the Mentawai Islands off the west coast of Sumatra in Indonesia. It is south of Sipura and north of South Pagai Island....

) and Borneo

Borneo

Borneo is the third largest island in the world and is located north of Java Island, Indonesia, at the geographic centre of Maritime Southeast Asia....

. The type locality, designated by lectotype

Lectotype

In botanical nomenclature and zoological nomenclature, a lectotype is a kind of name-bearing type. When a species was originally described on the basis of a name-bearing type consisting of multiple specimens, one of those may be designated as the lectotype...

, is listed as "Khasi Hills

Khasi Hills

The Khasi Hills are part of the Garo-Khasi range in the Indian state of Meghalaya, and is part of the Patkai range and of the Meghalaya subtropical forests ecoregion...

, Assam

Assam

Assam , also, rarely, Assam Valley and formerly the Assam Province , is a northeastern state of India and is one of the most culturally and geographically distinct regions of the country...

" (India).

Gumprecht et al. (2004) consider records for Bangladesh

Bangladesh

Bangladesh , officially the People's Republic of Bangladesh is a sovereign state located in South Asia. It is bordered by India on all sides except for a small border with Burma to the far southeast and by the Bay of Bengal to the south...

, Cambodia

Cambodia

Cambodia , officially known as the Kingdom of Cambodia, is a country located in the southern portion of the Indochina Peninsula in Southeast Asia...

 and Vietnam to be highly questionable, as they are likely based on misidentifications involving other species of Trimeresurus

Trimeresurus

Trimeresurus is a genus of venomous pitvipers found in Asia from Pakistan, through India, China, throughout Southeast Asia and the Pacific Islands. Currently 35 species are recognized...

.

Subspecies

Subspecies	Taxon author	Authority	Geographic range
T. p. barati Trimeresurus popeorum barati Trimeresurus popeorum barati is a venomous pitviper subspecies found in Indonesia.-Description:The scalation includes 17-19 rows of dorsal scales at midbody, 142-157/146-160 ventral scales in males/females, 62-72/55-58 subcaudal scales in males/females and 9-11 supralabial scales.-Geographic...	Regenass & Kramer, 1981	Barat bamboo pitviper	Indonesia Indonesia Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an... : Sumatra Sumatra Sumatra is an island in western Indonesia, westernmost of the Sunda Islands. It is the largest island entirely in Indonesia , and the sixth largest island in the world at 473,481 km2 with a population of 50,365,538...  (Barat District), the Mentawai Archipelago Mentawai Islands The Mentawai Islands are a chain of about seventy islands and islets off the western coast of Sumatra in Indonesia. Siberut is the largest of the islands. The other major islands are Sipura, North Pagai and South Pagai . The islands lie approximately 150 km off the Sumatran coast, across the...  (on Siberut Siberut Siberut is the largest and northernmost of the Mentawai Islands, lying 150 kilometres west of Sumatra in the Indian Ocean. A part of Indonesia, the island is the most important home for the Mentawai people. The western half of the island was set aside as the Siberut National Park in 1993... , North Pagai North Pagai North Pagai is one of the Mentawai Islands off the west coast of Sumatra in Indonesia. It is south of Sipura and north of South Pagai Island....  and South Pagai South Pagai South Pagai is one of the Mentawai Islands off the west coast of Sumatra in Indonesia. It is south of North Pagai Island... ), and Simeulue Simeulue Simeulue Regency is a regency in the Aceh province of Indonesia. It occupies the whole island of Simeulue , 150 km off the west coast of Sumatra, with a population of 80,279 ....  (Simalur).
T. p. popeorum	M.A. Smith Malcolm Arthur Smith Malcolm Arthur Smith was a herpetologist and physician working in the Malay Peninsula.-Early life:He was interested in reptiles and amphibians from an early age... , 1937	Pope's bamboo pitviper	Northeastern India India India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world... , Burma, Thailand Thailand Thailand , officially the Kingdom of Thailand , formerly known as Siam , is a country located at the centre of the Indochina peninsula and Southeast Asia. It is bordered to the north by Burma and Laos, to the east by Laos and Cambodia, to the south by the Gulf of Thailand and Malaysia, and to the... , West Malaysia, Singapore Singapore Singapore , officially the Republic of Singapore, is a Southeast Asian city-state off the southern tip of the Malay Peninsula, north of the equator. An island country made up of 63 islands, it is separated from Malaysia by the Straits of Johor to its north and from Indonesia's Riau Islands by the...  and Laos Laos Laos Lao: ສາທາລະນະລັດ ປະຊາທິປະໄຕ ປະຊາຊົນລາວ Sathalanalat Paxathipatai Paxaxon Lao, officially the Lao People's Democratic Republic, is a landlocked country in Southeast Asia, bordered by Burma and China to the northwest, Vietnam to the east, Cambodia to the south and Thailand to the west... .
T. p. sabahi Trimeresurus popeorum sabahi Trimeresurus popeorum sabahi is a venomous pitviper subspecies found on Borneo.-Description:The scalation includes 21 rows of dorsal scales at midbody, 149-157/148-156 ventral scales in males/females or 148-159 in general, 72-76/59-65 subcaudal scales in males/females and 9-11 supralabial...	Regenass & Kramer, 1981	Sabah bamboo pitviper	East Malaysia East Malaysia East Malaysia, also known as Malaysian Borneo, is the part of Malaysia located on the island of Borneo. It consists of the Malaysian states of Sabah and Sarawak, and the Federal Territory of Labuan. It lies to the east from Peninsular Malaysia , which is located on the Malay Peninsula. The two are...  (Sabah Sabah Sabah is one of 13 member states of Malaysia. It is located on the northern portion of the island of Borneo. It is the second largest state in the country after Sarawak, which it borders on its southwest. It also shares a border with the province of East Kalimantan of Indonesia in the south...  and Sarawak Sarawak Sarawak is one of two Malaysian states on the island of Borneo. Known as Bumi Kenyalang , Sarawak is situated on the north-west of the island. It is the largest state in Malaysia followed by Sabah, the second largest state located to the North- East.The administrative capital is Kuching, which... ) and Indonesia (Kalimantan Kalimantan In English, the term Kalimantan refers to the Indonesian portion of the island of Borneo, while in Indonesian, the term "Kalimantan" refers to the whole island of Borneo.... ).

Taxonomy

There are differences in opinion as to the correct spelling of the specific epithet. The following is from David and Vogel (1996):

This species was named in honour to Clifford H. Pope and Sarah H. Pope. The original spelling of the specific epithet, popeiorum, was corrected into popeorum by Smith (1943:518) on the basis that it was indeed a clerical error. Unfortunately, according to the Art. 32 (c, ii) of the Code (ICZN

International Code of Zoological Nomenclature

The International Code of Zoological Nomenclature is a widely accepted convention in zoology that rules the formal scientific naming of organisms treated as animals...

, 1985), such a change does not fall into the category of a “correction of an incorrect original spelling." According to the Art. 33 (d), the use of a termination -orum in a subsequent spelling of a species-group name that is a genitive based upon a personal name in which the correct original spelling terminates with -iorum, is an incorrect subsequent spelling, even if the change is deliberate. The original spelling, popeiorum, must therefore be conserved.