The Largest Snake That Ever Existed

Prehistoric snake was as long as a school bus. 

The largest snake that ever existed was Titanoboa cerrejonensis, a giant boid snake that lived during the Paleocene epoch, about 60 million years ago. It is estimated to have grown up to 42.7 feet long (13 meters) and weighed up to 2,500 pounds (1,135 kilograms). 

Some 60 million years ago, well after the demise of the dinosaurs, a giant relative of today’s boa constrictors, weighing more than a ton and measuring 42 feet long, hunted crocodiles in rain-washed tropical forests in northern South America.

Fossils of the snake were uncovered from the Cerrejón Formation at Cerrejón, the tenth biggest coal mine in the world in the Cesar-Ranchería Basin of La Guajira, northern Colombia, covering an area larger than Washington, D.C.

The Largest Snake That Ever Existed. Life-sized model of Titanoboa devouring a crocodilian, from the Smithsonian exhibit

Fossils of Titanoboa have been found in the Cerrejón Formation, and date to around 58 to 60 million years ago. The giant snake lived during the Middle to Late Paleocene epoch, a 10-million-year period immediately following the Cretaceous-Paleogene extinction event.

The only known species is Titanoboa cerrejonensis, the largest snake ever discovered, which supplanted the previous record holder, Gigantophis.

By comparing the sizes and shapes of its fossilized vertebrae to those of extant snakes, researchers estimated that the largest individuals of T. cerrejonensis found had a total length around 12.8 m (42 ft) and weighed about 1,135 kg (2,500 lb; 1.12 long tons; 1.25 short tons).

Titanoboa inhabited the first recorded Neotropical forest in the world. It shared its ecosystem with large Crocodylomorpha and large turtles, which may have served as food for the giant snake, except large sized Purusaurus brasiliensis, for example, too big for Titanoboa to handle. 

Unlike some contemporary poisonous snakes, Titanoboa wouldn't have benefited from brightly colored markings. The giant snake hunted by sneaking up on its prey. Most of the plus-size reptiles in Titanoboa's habitat were algae-colored and difficult to see against the landscape, making it easier to find dinner.