The green anaconda is the world’s heaviest and one of the world’s longest snakes, reaching 5.21 m (17.1 ft) long. More typical mature specimens reportedly can range up to 5 m (16.4 ft), with the females, at around a mean length of 4.6 m (15.1 ft), being generally much larger in adulthood than the male, which averages around 3 m (9.8 ft). Weights are less well studied, though will reportedly range from 30 to 70 kg (66 to 154 lb) in an average-range adult. It is the largest snake native to the Americas. Although it is slightly shorter than the reticulated python, it is far more robust: the bulk of a 4.5m green anaconda would be comparable to a 7.4m reticulated python. Eunectes murinus is probably the heaviest extant species of snake or squamate in the world, perhaps only rivaled by the Komodo dragon. Reports of anacondas 35–40 feet or even longer also exist, but such claims need to be regarded with caution, as no specimens of such lengths have ever been deposited in a museum and hard evidence is lacking. A $50,000 cash reward is offered for anyone who can catch an anaconda 30 ft (9.1 m) or longer, but the prize has not been claimed yet. The longest (and heaviest) verified specimen encountered by Dr. Jesús Antonio Rivas, who had examined thousands of anacondas, was a female measuring 5.21 m (17.1 ft) long and weighing 97.5 kg (215 lb).
Close-up of head
The color pattern consists of olive green background overlaid with black blotches along the length of the body. The head is narrow compared to the body, usually with distinctive orange-yellow striping on either side. The eyes are set high on the head, allowing the snake to see out of the water while swimming without exposing its body.
The remote location of the snake’s habitat has historically made locating, capturing, and returning specimens difficult. Transporting very large specimens to museums, especially before substantial decay, is difficult (though this has not prevented the return of much larger and more cumbersome crocodilian specimens). Skins can stretch substantially, increasing the snake’s size by more than 50% if stretched during the tanning process. Reports without physical proof are considered dubious if from nonscientists, as such individuals may at worst be more interested in promoting themselves or telling a good tale, or at the least may not be sufficiently trained in proper measurement methods. Observational reports of animals which were not captured are even more dubious, as even trained scientists often substantially overestimate the size of anacondas prior to capture. According to the Guinness Book of World Records, this species has been perhaps subject to the most extreme size exaggerations of any living animal. At the same time, it is difficult to argue a maximum possible or plausible size, because anacondas are known to continue to grow throughout their lives. Older reports in particular could include individuals which, in times of less pressure from humans, lived longer lives and thus reached greater sizes