Golden Lancehead

The island-dwelling golden lancehead snake is one of the most venomous snakes in the world.

It only lives on one island 30 miles off the coast of Brazil and eats birds primarily. This is a slender pit viper with a golden color and a spearhead-shaped head.

Rumors say that it caused the deaths of a lighthouse keeper and his family in the 1920s, but it’s not documented.

3 Amazing Facts About Golden Lanceheads

• One gram of their venom can cost more than one gram of gold.
• Scientists say that their venom is 3-5 times more toxic than other lancehead species.
• They are one of the few lanceheads that are at least partly arboreal.

Where to Find Golden Lanceheads

Golden lancehead snakes only live on one island off the coast of Brazil – Ila Queimada Grande, known to most of the world as Snake Island. They live in a variety of habitats on the island, from rocky hills to subtropical forests.

About Snake Island

Ila Queimada Grande, which translates as the Island of the Big burn, used to be connected to mainland Brazil, but at the end of the last ice age, the world’s sea levels rose and isolated it from the rest of South America. The animals trapped here suddenly had both an opportunity and a challenge.

For some reason, when the water levels rose, there weren’t any land predators or mammals. They had to change if they were to survive – and change they did!

While there weren’t any land mammals for prey, there were birds. Lots of birds. So the snakes took to the trees and developed a venom that takes them down quickly.

Fast forward 11,000 years, and you have a 106-acre island 30 miles off the coast of Brazil that is home to snakes, birds, insects, and little else. Golden lanceheads only live in the forested part, an area of about 63 acres.

Today, the only people allowed to visit the island are the Brazilian military, who maintain the lighthouse, and researchers with special permission from the Brazilian government.

Scientific Name

This snake’s scientific name describes both the type of snake and where they live. Bothrops is Greek and means pit face, while insular means island; fitting, as they live on an island.

Their common name, golden lancehead, refers to their head shape and color. These snakes have golden bellies and spearhead-shaped heads. Bothrops insularis, the sole species of known Golden Lancehead, is only found on Ilha da Queimada Grande, an island off the coast of So Paulo state in Brazil. An earlier French name for the genus, fer-de-lance, means the same, but scientists now apply it to only a couple of species.

Evolution and Origins

The Golden Lancehead, also known as Bothrops Insularis, is a venomous pit viper that is found exclusively on Ilha da Queimada Grande, an island located off the coast of São Paulo state in Brazil.

The population of Golden Lancehead snakes on Snake Island is estimated to be around 2,000 to 4,000 individuals, and since this island is the only known habitat for this species, the snakes have been classified as Critically Endangered on the IUCN Red List.

Additionally, this snake sometimes gets confused with the pit viper. So, here are a few differences: golden lanceheads are distinct from other pit vipers in terms of their size, venom, and appearance, as they are relatively small, measuring only 4 feet in length, have potent venom that can be lethal to humans, and are recognizable for their yellow skin.

Population and Conservation Status

The golden lancehead snakes have a population of between 2,000 and 4,000 on Snake Island. This is the only place in the world you’ll find these snakes, and in light of this fact, they’re on the IUCN Redlist as Critically Endangered.

At one point, people burned the vegetation on the island to try to kill off the snakes and start a banana plantation. Unfortunately for them, the snakes hid in crevices until the flames died down. The snake population suffered, and the areas that burned are growing back, but it may yet be decades before the forests recover completely.

Brazilian military maintains a lighthouse on the island, and they have removed a lot of the trees and vegetation where the snakes hide. This did some damage to the population, but it’s the poachers who are the biggest unknown.

Poachers and the $30,000 Catch

Some scientists believe that poachers are doing the most damage to the population. Golden lancehead snakes are so valuable in the illegal pet trade and scientific research that poachers visit the island illegally to try to capture and sell them.

One specimen can come with a paycheck of $10,000 to $30,000, depending upon the age and health. To some smugglers, that’s a worthy payoff for the risk of an agonizing death.

However, studies aren’t conclusive because snake populations are difficult to accurately observe. A study published in 2014 concluded that their primary challenges to survival are food and reproduction.

They observed that males seemed to have a higher survival rate than females and believe it may be due to the higher quantity of resources that females require for breeding.

Appearance and Description

These snakes measure between two and four feet as adults. There isn’t much data on juveniles; however, their closest relative, the yarara (B. jararaca), produces offspring that average about 12 inches long. So, this seems like a reasonable estimate.

They are slender snakes, and the golden lanceheads’ color ranges from yellowish to light golden brown with darker irregular markings along the length of their back. Their markings are mostly triangular, with somewhat squarish markings interspersed in between.

These snakes have a sharply angular head that is reminiscent of a spearhead (hence its name), and yellow-gold eyes with elliptical pupils.

Venom: How Dangerous are They?

This snake is one of the most venomous species in the world. While no one on record has ever died from a bite from a golden lancehead, scientists estimate that an untreated bite may carry a 7% fatality rate. They base this on the mortality rate for other lancehead species bites.

Golden lancehead snakes evolved a highly toxic and fast-acting venom. Some say that it melts human flesh, but this is most likely an exaggeration. However, according to research, it is up to 5% more toxic than that its mainland cousins.

Their venom contains hemotoxic venom that helps the snake digest their food. It causes pain and swelling around the bite, nausea and vomiting, blood in the vomit and urine, bruising, intestinal bleeding, kidney failure, brain hemorrhage, and severe death of muscular tissue. Some say that those bitten and envenomated by a golden lancehead snake could die within six hours.

Scientific Research

Lancehead snake venom (Bothrops Atrox) has contributed to medicines for high blood pressure and clotting disorders.

Venom from this snake and other venomous snakes is valuable to scientists. Several medical advancements have come from research performed on snake venom. Researchers believe that this species holds even more promise for medical research.

Behavior and Humans

This snake eats primarily birds, but younger snakes may also eat smaller prey such as lizards or nestlings. Most often, golden lancehead snakes eat tyrant flycatchers, a passerine bird on the island. There’s some evidence, based on damaged tails and observed behavior, that the species uses some form of caudal luring to entice their prey close enough to strike.

Due to the isolated nature of the golden lancehead population, human interactions are exceedingly rare, and almost always intentional (either researchers or poachers).

Similar Animals

• Fer-de-Lance
• Bushmaster 
• Cascabel

1. Reptile Database, Available here: https://reptile-database.reptarium.cz/species?genus=Bothrops&species=insularis
2. The golden lancehead Bothrops insularis (Serpentes: Viperidae) relies on two seasonally plentiful bird species visiting its island habitat | Otavio A. V. Marques, Marcio Martins, Pedro F. Develey, Arthur Macarrão & Ivan Sazima, Available here: https://www.tandfonline.com/doi/abs/10.1080/00222933.2011.654278
3. Population Dynamics of the Critically Endangered Golden Lancehead Pitviper, Bothrops insularis: Stability or Decline? | Murilo Guimarães, Roberto Munguía-Steyer, Paul F. Doherty J, Marcio Martins, Ricardo J. Sawaya, Available here: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0095203#s3
4. (1970)