''Dendrelaphis ngansonensis'', commonly known as either the Nganson bronzeback or Nganson bronzeback tree snake, is a

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), ...

of snake in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Colubridae Colubridae (, commonly known as colubrids , from , 'snake') is a family of snakes. With 249 genera, it is the largest snake family. The earliest fossil species of the family date back to the Late Eocene epoch, with earlier origins suspected. C ...

, sound in

Southeast Asia Southeast Asia is the geographical United Nations geoscheme for Asia#South-eastern Asia, southeastern region of Asia, consisting of the regions that are situated south of China, east of the Indian subcontinent, and northwest of the Mainland Au ...

Etymology

The species name ''ngansonensis'' is named after the type locality of the Ngân Sơn district of

Tonkin Tonkin, also spelled Tongkin, Tonquin or Tongking, is an exonym referring to the northern region of Vietnam. During the 17th and 18th centuries, this term referred to the domain '' Đàng Ngoài'' under Trịnh lords' control, including both the ...

, North

Vietnam Vietnam, officially the Socialist Republic of Vietnam (SRV), is a country at the eastern edge of mainland Southeast Asia, with an area of about and a population of over 100 million, making it the world's List of countries and depende ...

Taxonomy

''Dendrelaphis ngansonensis'' belongs to the

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 ...

Dendrelaphis ''Dendrelaphis'' is a genus of snakes in the subfamily Ahaetuliinae of the family Colubridae. Species of the genus ''Dendrelaphis'' are distributed from Pakistan, India and southern China to Indonesia, Timor-Leste, the Philippines, Australia, Ne ...

'', which contains 48 other described species.. ''D. ngansonensis'' is most closely related to ''

Dendrelaphis cyanochloris ''Dendrelaphis cyanochloris'', commonly known as Wall's bronzeback or the blue bronzeback, is a species of colubrid snake found in Southeast Asia. Taxonomy ''Dendrelaphis cyanochloris'' belongs to the genus ''Dendrelaphis'', which contains 48 ...

'', and together the two might form a

species complex In biology, a species complex is a group of closely related organisms that are so similar in appearance and other features that the boundaries between them are often unclear. The taxa in the complex may be able to hybridize readily with each oth ...

. ''Dendrelaphis'' is one of five genera belonging to the vine snake

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end botanical subfamily names with "-oideae", and zo ...

Ahaetuliinae, of which ''Dendrelaphis'' is most closely related to '' Chrysopelea'', as shown in the

cladogram A cladogram (from Greek language, Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an Phylogenetic tree, evolutionary tree because it does not s ...

below:

Distribution

The species is found in

Laos Laos, officially the Lao People's Democratic Republic (LPDR), is the only landlocked country in Southeast Asia. It is bordered by Myanmar and China to the northwest, Vietnam to the east, Cambodia to the southeast, and Thailand to the west and ...

Thailand Thailand, officially the Kingdom of Thailand and historically known as Siam (the official name until 1939), is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. With a population of almost 66 million, it spa ...

Cambodia Cambodia, officially the Kingdom of Cambodia, is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. It is bordered by Thailand to the northwest, Laos to the north, and Vietnam to the east, and has a coastline ...

, and southwestern China (

Yunnan Yunnan; is an inland Provinces of China, province in Southwestern China. The province spans approximately and has a population of 47.2 million (as of 2020). The capital of the province is Kunming. The province borders the Chinese provinces ...

Habitat and behaviour

''Dendrelaphis ngansonensis'' is an

arboreal Arboreal locomotion is the locomotion of animals in trees. In habitats in which trees are present, animals have evolved to move in them. Some animals may scale trees only occasionally (scansorial), but others are exclusively arboreal. The hab ...

snake that occurs in both primary and secondary forests. It preys upon small vertebrates. It has been found to be both diurnal and

nocturnal Nocturnality is a ethology, behavior in some non-human animals characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnality, diurnal meaning the opposite. Nocturnal creatur ...

, and has

oviparous Oviparous animals are animals that reproduce by depositing fertilized zygotes outside the body (i.e., by laying or spawning) in metabolically independent incubation organs known as eggs, which nurture the embryo into moving offsprings kno ...

reproduction.

References

ngansonensis Snakes of Southeast Asia Reptiles of Cambodia Snakes of China Reptiles of Laos Reptiles of Thailand Snakes of Vietnam Reptiles described in 1935 Taxa named by René Léon Bourret {{Colubrid-stub