Trimeresurus venustus is a snake species that has gradually been found in many locations across Southern Thailand and Northern Malaysia. Here in Krabi we have a number of locations where it can be found.
If you would like to attempt to find this snake on your own in Thailand – read on.
If you have limited time,
Book a Night Safari to find this and other snakes >
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Trimeresurus venustus (Brown-spotted Green Pit Viper)
Also known as: Beautiful Pit Viper, Cryptelytrops venustus (former classification).
Quick Snake Facts
- Thai Name: งูหางแฮ่มใต้ – in english – ngoo hang ham dty (snake dry south).
- Local Name: Haang Ham tai
- Average Length: 40-70 cm and usually on the lower end of that range
- Geographic Range: Southern Thailand (Chumphon to Satun Province)
- Conservation Status: Not currently listed on IUCN Red List
- Antivenom Code: SAsTRC01
Physical Description
The Brown-spotted Green Pit Viper is characterized by its vibrant green coloration with distinctive brown or reddish-orange scales that may form bands across its body. Key identifying features include:
- Triangular-shaped head typical of pit vipers
- Strongly keeled dorsal scales
- Dorsal scale count: 21-21-15
- Heat-sensing pits between the eyes and nostrils
Habitat & Distribution
- Elevation range: 0-300 meters
- Primary and secondary rainforest
- Limestone mountains and formations
- Rubber tree plantations
- Currently confirmed in Krabi, Surat, Phang Nga, Nakhon Si Thammarat, Satun, and Pattalung provinces
Where to Find the Brown-spotted Pit Viper in Thailand
Suratthani Province – Take a train down from Bangkok. Stop at Phunpin Station. Take the orange bus to Surat Town. Rent a motorbike. Go to this temple. Climb the stairs up the hill. Find these snakes in the low bushes during the day – sleeping. This is where we first found this snake in Thailand.
- Khanom (Surat) – this small area has lot of the brown-spotted pit vipers and it is easy to get to with a rented motorbike or car from town or with a bus or taxi.
Satun Province – Go to Thaleban National Park at the Wang Prachan Border. Stay overnight. Find this snake on the steep hilly sections you find on the footpath.
Krabi Province – Go to the Tiger Cave Temple. Climb the short set of stairs up then down into the foothills area. Take the path to the right at the bottom of the stairs. Find them sleeping on low bushes in daytime.
- Phanom Bencha Mountain Resort – Find these snakes in the low vegetation on rocks on the left side of the main path leading to the big water reservoir at night.
- Wat Tum Sang Phet – this temple has a lot of T. venustus you can find in the daytime, temple is closed at night. Find them at the base of the steep rocky limestone on the opposite side of the hill from the entrance. Pull in. Park. Enter. Go to the right counterclockwise around the hill on the path. The snakes are on the low vegetation below the path. There can be some dogs that might be a problem.
- National Park at the Waterfall – Stay overnight and walk along the trails to and around the waterfall. The brown-spotted pit vipers can be found on the trail especially at the base of rocky hills with obvious limestone rocks.
Best Time of Year to Find the Brown-Spotted Pit Viper in Thailand
The best time of year to find these snakes is from May to December each year. This is during an average year when the rain cycles don’t extend much beyond December. There are times during January to April that we can find them, but you’ll have to contact us to see if we currently know where they are.
Best Option for Finding the T. venustus Green Pit Viper?
We can usually show you were some of these snakes are throughout the year. Recently we found an area that seems to hold them even during the dry season. If you’re targeting T. venustus, ask us if we know where any are. We can possibly take you there on a Night Safari to target that and other snakes or animals.
Brown-Spotted Pit Viper Behavior
Activity Patterns
- Primarily nocturnal but also active or hunting in ambush mode on very cloudy and especially rainy days.
- Increased daytime activity following heavy rainfall
- Often found in ambush position in rain catches and near ground level
- Rests in vegetation during daylight hours from 1-4 meters off the ground
Hunting & Diet
- Main prey: Frogs, small geckos, and skinks
- Utilizes heat-sensing pits to detect warm-blooded prey
- Less likely to target cold-blooded prey like geckos
- Primarily terrestrial hunting strategy
Defensive Behavior
- Generally non-aggressive and not known to be excessively bitey
- Relatively slow-moving when disturbed until really threatened and they will move fast
- Will bite if seriously provoked or handled
- Benefits from avoidance rather than intervention
Reproduction
- Viviparous (live-bearing)
- Gestation period: Approximately 2-3 months
- Clutch size: 20-30 offspring
- Young born in protective jelly-like membrane
- Offspring display adult coloration and patterns at birth
- Breeding may occur multiple times per year (updated from previous June/July-only assumption)
Venom & Medical Significance
Venom Characteristics of T. venustus
- Moderate toxicity
- Primary symptoms include localized pain and swelling
- Serious effects possible with prolonged envenomation
- All bites should be treated as potentially dangerous
Treatment
Green Pit Viper Antivenin is available at most Thai public hospitals:
- Manufacturer: Science Division, Thai Red Cross Society
- Provider: Queen Saovabha Memorial Institute
- Address: 1871 Rama IV Road, Pathumwan, Bangkok 10330
- Contact: +66-2-252-0161 to 0164
Taxonomic Classification
- Kingdom: Animalia
- Phylum: Chordata
- Class: Reptilia
- Order: Squamata
- Suborder: Serpentes
- Family: Viperidae
- Subfamily: Crotalinae
- Species: Trimeresurus venustus
Research Updates (2015-2024)
- Recent molecular studies have confirmed its placement within Trimeresurus
- Growing evidence suggests more variable breeding patterns than previously thought
- Increased documentation of urban adaptation, particularly around temple grounds
- Greater understanding of venom composition and medical management
- Observations of successful adaptation to disturbed habitats, including agricultural areas
Conservation Notes
While not currently listed as threatened, the species faces increasing pressure from:
- Habitat fragmentation
- Urban development
- Collection for pet trade – unfortunately this has become a problem. Thai National Park Rangers randomly check bags of people coming out of the rainforests in Krabi, Khanom, and at some of the national parks. Penalties are huge and include jail time and deportation.
- Human-snake conflicts in developed areas
Go on a NIGHT WALK for SNAKES! >
