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Viperidae

Kramer's Pit Viper

Venomous

Trimeresurus macrops

Kramer's Pit Viper
Trimeresurus macrops, © Jay Paroline
Kramer's Pit ViperKramer's Pit ViperKramer's Pit ViperKramer's Pit ViperKramer's Pit Viper

6 photographs of the Kramer's Pit Viper. © Jay Paroline.

The Kramer's Pit Viper (Trimeresurus macrops) is a venomous snake in the Viperidae family, recorded in 5 countries.

If you are bitten

This is a venomous snake. Treat any bite as a medical emergency: stay calm, keep the bitten limb still and roughly level with the heart, remove rings and tight clothing, and get to emergency care immediately. Do not apply a tourniquet, cut the wound, apply ice, or try to suck out venom. Call your local emergency number or poison center.

Family
Viperidae
Danger
high

About the Kramer's Pit Viper

Trimeresurus macrops is a venomous pit viper species endemic to Southeast Asia. No subspecies are currently recognized. Common names include large-eyed pitviper, green pit viper, and Kramer's pit viper.

Description

It can be distinguished from other green pit vipers by the relatively large size of its eyes, which is especially noticeable in adult specimens, and to which the specific name, macrops, refers.

Breeding

According to Strine, Green pit vipers mate during the end of the rainy season, between September and October. Female vipers will pull male vipers up the tree and begin mating.

Geographic range

It is found in Southeast Asia in northern Cambodia, Laos, Thailand, and southern Vietnam. The type locality given is "Bangkok, Thailand".

Venom

T. macrops belongs to the genus Trimeresurus, a group of Asian vipers with primarily hemotoxic venom — a type of venom that can destroy blood cells, disrupt blood clotting, and damage organ function. A bite from this viper's better-studied cousin, the white-lipped pit viper, is said to cause effects ranging from mild envenomation to death. The broader viper family, Viperidae, includes some of the deadliest snakes in the world, responsible for more human fatalities than any other type of snake.

Adapted from Wikipedia, available under CC BY-SA.

Frequently asked: Kramer's Pit Viper

Is the Kramer's Pit Viper venomous?
Yes. The Kramer's Pit Viper (Trimeresurus macrops) is venomous and belongs to the Viperidae family (viper). Its bite is considered high risk to people. Treat any bite as a medical emergency.
Is the Kramer's Pit Viper poisonous?
Snakes are venomous, not poisonous. "Poisonous" means harmful to eat or touch; "venomous" means injecting toxins through a bite. The Kramer's Pit Viper is venomous, delivering venom through a bite.
Is the Kramer's Pit Viper dangerous?
This is a venomous snake. Treat any bite as a medical emergency: stay calm, keep the bitten limb still and roughly level with the heart, remove rings and tight clothing, and get to emergency care immediately. Do not apply a tourniquet, cut the wound, apply ice, or try to suck out venom. Call your local emergency number or poison center.
Where does the Kramer's Pit Viper live?
The Kramer's Pit Viper has verified records in 5 countries, including Thailand, Cambodia, Lao People’s Democratic Republic. See the distribution section below for its full range.

If you are bitten by the Kramer's Pit Viper

A venomous snakebite is a medical emergency. Call your local emergency number immediately. In the US, dial 911 or Poison Control at 1-800-222-1222.

Do

  • Get away from the snake and stay calm. Most bites worsen when people panic or try again to handle the snake.
  • Call 911 or Poison Control (1-800-222-1222) right away. Antivenom works best when given early.
  • Note the time of the bite and, from a safe distance, the snake's color and pattern, a phone photo is enough. Do not chase it.
  • Keep the bitten limb still and at roughly heart level. Sit or lie down and limit movement.
  • Remove rings, watches, and tight clothing near the bite before swelling starts.
  • Gently wash the bite with soap and water and cover it with a clean, dry dressing.

Do not

  • Do not cut the wound or try to suck out the venom.
  • Do not apply a tourniquet or ice.
  • Do not drink alcohol or caffeine.
  • Do not take aspirin or ibuprofen, they can worsen bleeding. Acetaminophen is safer for pain.
  • Do not try to catch or kill the snake. A dead snake can still bite by reflex.

First-aid guidance adapted from the U.S. Centers for Disease Control and Prevention (CDC NIOSH), Venomous Snakes. Educational only; always follow the instructions of emergency responders.

Where it is found

ThailandCambodiaLao People’s Democratic RepublicViet NamMyanmar

More Viperidae snakes

Classification

How scientists group this snake, from the broadest category down to the exact species. Each step narrows to its closest relatives.

OrderThe broad group of scaled reptiles: all snakes and lizards
Squamata
FamilyA group of related snakes that share key traits
Viperidae
GenusA close-knit group of very similar species
Trimeresurus
SpeciesThis exact snake, named in the two-part scientific name
Trimeresurus macrops

Keep learning

Distribution from GBIF & iNaturalist. Venom status per CDC. Background: Wikipedia. Informational only. Never handle a snake to identify it.