Īlmost all specimens in excess of 6 m (20 ft), including a much-publicized specimen allegedly 11.36 m (37 ft 3 in) long, have no voucher specimens including skins or bones. The team's guesses ran from 6.1 to 18.3 m (20 ft 0 in to 60 ft 0 in) when measured, this specimen was found to be 5.9 m (19 ft 4 in). To prove the point of overestimating, in Guyana in 1937, zoologist Alpheus Hyatt Verrill asked the expedition team he was with to estimate the length of a large, curled-up anaconda on a rock. Numerous estimates and second-hand accounts abound, but are generally considered unreliable. Several zoologists (notably Henry Walter Bates and Alfred Russel Wallace, among others) note rumors of snakes beyond 9 or 12 m (30 or 40 ft) long, but in each case, their direct observations were limited to snakes around 6 m (20 ft) in length. Numerous historical accounts of green anacondas are reported, often of improbable sizes. According to the Guinness Book of World Records, this species has been perhaps subject to the most extreme size exaggerations of any living animal. 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. Reports without physical proof are considered dubious if from non-scientists, 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. Skins can stretch substantially, increasing the snake's size by more than 50% if stretched during the tanning process. 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). The remote location of the snake's habitat has historically made locating, capturing, and returning specimens difficult. Difficulties in determining maximum size The digestion process takes many days to complete and during this time the anaconda behaves very sluggishly. The windpipe in its mouth allows it to breathe while swallowing its prey. This allows it to swallow prey larger than the size of its head. The anaconda's jaw bones splay open at the front because they are loosely connected.

The eyes are set high on the head, allowing the snake to see out of the water while swimming without exposing its body. The head is narrow compared to the body, usually with distinctive orange-yellow striping on either side. The color pattern consists of an olive green background overlaid with black blotches along the length of the body. In 1937, a specimen shot in Guyana was claimed to have measured 5.9 m (19 ft 4 in) long and weighed 163 kg (359 lb 6 oz). Jesús Antonio Rivas, who had examined more than 1,000 anacondas, was a female 5.21 m (17 ft 1 in) long and weighing 97.5 kg (214 lb 15 oz). The longest and heaviest verified specimen encountered by Dr. Reports of anacondas 11–12 m (35–40 ft) or even longer also exist, but such claims must be regarded with caution, as no specimens of such lengths have ever been deposited in a museum and hard evidence is lacking. Although it is slightly shorter than the reticulated python, it is far bulkier the bulk of a 5.2-metre (17 ft 1 in) green anaconda is comparable to that of a 7.4-metre (24 ft 3 in) reticulated python. It is the largest snake native to the Americas. Weights are less well studied, though reportedly range from 30 to 80 kg (66 to 176 lb) in a typical adult. More typical mature specimens reportedly can range up to 5 m (16 ft 5 in), with adult females, with a mean length of about 4.6 m (15 ft 1 in), being generally much larger than the males, which average around 3 m (9 ft 10 in). The green anaconda is the world's heaviest and one of the world's longest snakes, reaching a length of up to 5.21 m (17 ft 1 in) long.

The green anaconda's specific name is derived from the Latin murinus, meaning 'of mice', for being thought to prey on mice.ĭescription New England Aquarium Etymology įurther information on etymology of generic name: Eunectes § Etymology Fossils of the snake date back to the Late Pleistocene in the Gruta do Urso locality. The term ' anaconda' often refers to this species, though the term could also apply to other members of the genus Eunectes. Like all boas, it is a non-venomous constrictor. It is the largest, heaviest and the second longest (after the reticulated python) snake in the world. The green anaconda ( Eunectes murinus), also known as the giant anaconda, emerald anaconda, common anaconda, or common water boa, is a boa species found in South America and the Caribbean island of Trinidad.

Green anaconda size national geographic