To learn more about these snakes that went extinct, we’ll go over each snake’s appearance, behavior, range, and habitat. Then, we’ll examine why the species went extinct. The first three snakes on our list all lived up until recent times. But the top four on the list actually died out a very long time ago. We’ll finish up our list of snakes that went extinct with a snake that dwarfs every other snake ever to live. Read on to learn more about seven species of snakes that went extinct. Number one is terrifying!

7. Saint Croix Racer (Borikenophis sanctaecrucis)

Saint Croix racers were a species of snake found only on the island of Saint Croix in the United States Virgin Islands. They grew to a length of just over three feet and inhabited the island’s forested regions. As members of the Colubridae family of snakes, they laid eggs rather than giving birth to live young. Though not technically listed as extinct, no Saint Croix racers have been seen in a very long time. It’s highly likely that no specimens remain.

6. Hoffstetter’s Worm Snake (Madatyphlops cariei)

Back in the early twentieth century, scientists on the island of Mauritius unearthed the fossilized vertebrae of an extinct snake. Today, that snake has officially been named Hoffstetter’s worm snake. They were listed as extinct in 1994, though their extinction likely took place several hundred years before that. Little is known about these snakes, but they were almost certainly blind. Hoffstetter’s worm snakes would have had little to no defense when colonization introduced invasive species to the island.

5. Round Island Burrowing Boa (Bolyeria multocarinata)

The Round Island burrowing boa is yet another extinct snake from the island of Mauritius. These snakes were officially declared extinct in 1975, after decades of almost no sightings. Round Island burrowing boas had light brown bodies with darker splotches and pale pink undersides. As their name suggests, they spent their lives on or under the ground. Unfortunately for these snakes that went extinct, human habitation led to habitat loss and killing, which eventually caused the Round Island burrowing boa to go extinct.

4. Yurlunggur (Yurlunggur camfieldensis)

These snakes that went extinct were one of the largest snakes to roam Australia. They grew to an astonishing length of around twenty feet. Like modern-day pythons and anacondas, they constricted their prey to death with their massive bulk. Yurlunggurs went extinct during the Miocene era, which ended about five million years ago. So, though they were fearsome in their massive size, these snakes died out long before humans came on the scene. Yurlunggurs belonged to the extinct Madtsoiidae family of snakes, along with number three on our list of snakes that went extinct.

3. Wonambi (Wonambi naracoortensis)

The wonambi matched the yurlunggur in size; both snakes grew up to twenty feet. Some may have even grown longer. Like the yurlunggur, the wonambi was almost certainly a constrictor. They would have relied on ambushing and then squeezing their prey to death, like a python, rather than envenomating, like a rattlesnake. Wonambi lived in Australia well into the Anthropocene (the age of man). The first settlers to Australia would have encountered these giants and would have had to watch out for them. These snakes that went extinct died out sometime around 50,000 years ago. Scientists are divided as to whether or not humans contributed to the extinction of this massive snake.

2. Gigantophis (Gigantophis garstini)

Gigantophis went extinct about 40 million years ago. But, if they lived today, they would be absolutely terrifying. Based on fossil remains, these snakes that went extinct grew up to 35 feet long. Scientists believe they constricted their prey and would have had no trouble killing and eating medium to large-sized prey. Luckily for humans, they went extinct long before we existed. Gigantophis may have been huge, but number one on our list clocked in at even bigger.

1. Titanoboa (Titanoboa cerrejonensis)

Coming in at nearly 50 feet long, number one on our list of snakes that went extinct is the truly massive Titanoboa. Scientists aren’t sure exactly when these snakes went extinct, but it’s safe to say that they were around 60 million years ago. Despite their enormous size, they’re believed to have preyed specifically on fish. Like gigantophis, Titanoboas were constrictors and almost certainly lacked venom. Today, it’s unknown why Titanoboa went extinct. But, if they were alive today, they would easily be the longest and heaviest snakes in the world.