The heaviest snake alive is Eunectes murinus, commonly called the anaconda which normally grows to a maximum of approximately 20 ft (6 meters) in length, but sometimes develops as long as 25 feet (7.6 meters), and weighs around 100 pounds (45 kilograms). And, despite extensive searching, and sometimes even cash rewards of $50,000 offered by the Wildlife Conservation Society, no live snake longer than 30 feet (9.1 meters) has been found.
However, neither the reticulated python nor the anaconda can hold a candle in comparison to an ancient snake known as Titanoboa cerrejonensis. This giant snake lived in tropical rainforests that covered the area that is today the nation of Columbia. It inhabited this area during the Paleocene epoch, between about 60 million years ago and 58 million years back. In terms of size, Titanoboa is thought to have grown to approximately 43 feet (15 meters) in length, would have had a diameter of more than 1 meter (3 feet), and almost certainly weighed more than one ton.
Titanoboa, like most other big snakes, was non-venomous. On the contrary, it was an ambush predator that could have killed its prey by constriction. Titanoboa would lay motionless in wait until prey approached, and then suddenly and without warning, when the prey came within reach it’d pounce, wrap itself around its victim. Slowly and gradually, it would tighten its body around that of the victim, until the prey eventually suffocated to death.