Dendrelaphis ngansonensis
Silhouette: Alex Slavenko · PhyloPic
In 3 days ~40% in a week ~70%
Dendrelaphis ngansonensis, commonly known as either the Nganson bronzeback or Nganson bronzeback tree snake, is a species of snake in the family Colubridae, sound in Southeast Asia. The species name ngansonensis is named after the type locality of the Ngân Sơn district of Tonkin, North Vietnam.
Dendrelaphis ngansonensis belongs to the genus Dendrelaphis, which contains 48 other described species. D. ngansonensis is most closely related to Dendrelaphis cyanochloris, and together the two might form a species complex.
Dendrelaphis is one of five genera belonging to the vine snake subfamily Ahaetuliinae, of which Dendrelaphis is most closely related to Chrysopelea, as shown in the cladogram below: The species is found in Vietnam, Laos, Thailand, Cambodia, and southwestern China (Yunnan). Dendrelaphis ngansonensis is an arboreal snake that occurs in both primary and secondary forests. It preys upon small vertebrates. It has been found to be both diurnal and nocturnal, and has oviparous reproduction. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Cuc Phuong National Park | 🇻🇳 Vietnam | |
| 2 | Khao Yai National Park | 🇹🇭 Thailand | |
| 3 | Cat Tien National Park | 🇻🇳 Vietnam |
Possible
About 20% of wildlife watchers report a Vietnamese Bronzeback sighting in Khao Yai National Park on a given day, based on 20 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 23rd most-seen of the 46 reptiles we can rate there. Over three days the chance rises to about 40%, and over a week to about 70%, if each day is a fresh chance.
July and September
In those months about 30% of wildlife watchers report a Vietnamese Bronzeback in Khao Yai National Park on a given day, against under 5% in January, April and June, the lowest months. Those are among Khao Yai National Park's wettest months, with about 300 mm of rain a month against 15 mm in December.
Between 5 and 8 am
Across all the parks we cover, that three-hour window holds the most Vietnamese Bronzeback sightings with a recorded time, and about 7 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
2nd of 3
Of the 3 parks where we can rate Vietnamese Bronzeback sightings, Khao Yai National Park ranks 2nd at about 20%. The best odds are in Cuc Phuong National Park (Vietnam, about 30%).
Same family: Colubridae
The closest relatives of the Vietnamese Bronzeback that you can see in Khao Yai National Park (family Colubridae, Colubrid Snakes) are Oriental Whipsnake (about 30%), Yellow-Spotted Keelback (about 20%) and Chinese Ratsnake (about 20%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Vietnamese Bronzeback is recorded against all the reptiles logged in Khao Yai National Park (20 verified sightings from 2019 to 2026), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
