Green Anaconda (Eunectes murinus)
ReptileSnakeSouth America
A green anaconda lying in wait in the water in Apure state, Venezuela, with only its head showing.
Image: Daniel10ortegaven, CC BY-SA 3.0, via Wikimedia Commons.
Overview
The green anaconda (Eunectes murinus) is a heavy-bodied, semi-aquatic boa of tropical South America east of the Andes and the island of Trinidad. It is described as the heaviest snake in the world, and its females are much larger than its males — the greatest difference in size between the sexes of any land vertebrate.
It is olive-green to brown above, with round dark blotches along the back and a row of light-centered spots along each side, and its belly is yellow and black. The eyes and nostrils sit on top of the head, which helps it see and breathe while swimming, and a stripe — described as black, or as reddish brown to orange-cream edged with black — runs from each eye to the angle of the jaw.
How large it grows is disputed. One account gives maximum lengths of 6.6 m for females and 3.39 m for males and a maximum mass of 104.4 kg, while others give up to 8 m or 9 m and 250 kg; reports of 10–12 m are unconfirmed or disputed. A seven-year field study in the Venezuelan llanos found the largest snakes well below the maxima reported in the literature.
In 2024 a northern population was described as a separate species, Eunectes akayima; the Reptile Database provisionally treats it as a synonym of the green anaconda, so this profile covers both.
Habitat & Range
Green anacondas live in and beside fresh water — swamps, marshes, slow rivers and streams, lagoons, flooded forest, and seasonally flooded savannas and grasslands — in both rainforest and savanna regions. They prefer shallow, slow-moving water with medium to dense aquatic vegetation, although one account adds deep, turbid and clear lakes and rivers. Another puts them in the water about 86% of the time and at the water's edge the rest, and they seem to prefer water less than 50 cm deep.
The range covers the Amazon and Orinoco basins, the Guianas, the llanos of Venezuela and Colombia, the Cerrado of Brazil and Paraguay, and Trinidad.
Diet
The green anaconda is an opportunistic predator of any vertebrate it can kill and swallow — fish, amphibians, reptiles, birds and mammals. It usually waits submerged at the water's edge, with only its eyes and nostrils showing, for animals that come to drink, then holds the prey in its jaws and constricts it. Young anacondas eat mostly birds; large adults take capybaras, deer, peccaries, tapirs, caimans, sheep and calves.
Large prey usually weigh 14% to 50% of the snake's own mass, and after a large meal an anaconda may go weeks or months without eating. Some also eat carrion and other anacondas.
Behavior
Green anacondas appear to be active by day and night but avoid the hottest hours, and one account says they are most active in the early evening. They bask on sunny days — especially breeding females — and rest in crevices, caves, among the roots of water plants or deep in mud. Where wetlands dry out seasonally they must find water or burrow into mud and stay dormant through the dry period; snakes near rivers are active all year.
Outside the breeding season anacondas are mostly solitary, each keeping to its own hunting area. In the dry season in the Venezuelan llanos, though, as many as 34 may crowd around the last mud holes in a 10 × 20 m area.
Human Interaction & Conservation
Attacks on people are rare: there are accounts of predatory strikes but no well-documented deaths, and the bite is not venomous, although the curved teeth can tear flesh. People hunt anacondas — many fear them for their size, and some may kill them to protect livestock — and live snakes and skins are traded internationally under CITES Appendix II, though illegal trade persists. In the United States the species is listed as injurious wildlife, and snakes found in Florida are probably released or escaped pets.
IUCN's global assessment lists the green anaconda as Least Concern (2021).
Reproduction & Life Cycle
Anacondas mate in the dry season, in breeding aggregations where one female is courted by as many as 13 males at once; larger males seem to choose larger females, and females sometimes eat males after mating. The eggs hatch inside the mother, and the young are born live in shallow water after a gestation of several months — 7 months in two accounts, 6–7 or 6 to 10 months in others.
Litters usually number 20–40 young (28 to 42 in one account), with up to 82 recorded; litter size rises with the female's size, but larger females breed less often. Newborns average 200 g and measure 36–85 cm. Anacondas mature at about 3–4 years and, by one account, mate only every other year. Facultative parthenogenesis — development from unfertilized eggs — has been documented.
Wild anacondas live about 10 years on average; one recaptured after 13 years was estimated to be 20. The record in captivity is 31.8 years.
Sourced facts
Each value below is traced to the specific reference that states it. Open a row's evidence to see the source, where to look in it, and how firmly it supports the value. Sources checked 2026-10-20.
| Fact | What the source states | Evidence |
|---|---|---|
| Distinguishing traits | Heavy-bodied; olive-green to brown above with round dark blotches along the back and a row of light-centered spots on each side; belly yellow and black. Eyes and nostrils sit on top of the head, a stripe runs from each eye to the jaw, and the belly scales are very narrow.Females are much larger than males: breeding females are at least five times the size of breeding males, the greatest sexual size dimorphism of any land vertebrate. The eye stripe is described as black, or as reddish brown to orange-cream between thinner black stripes. Scales are smooth and glossy. The high-set eyes and nostrils help it see and breathe while swimming. | Matches source · Smithsonian's National Zoo and Conservation Biology Institute, Animal Diversity Web (University of Michigan Museum of Zoology), Reptiles of Ecuador (Arteaga 2024, in Arteaga, Bustamante & Vieira, eds.; Fundación Khamai and Tropical Herping), U.S. Geological Survey, Nonindigenous Aquatic Species Database — how we knowSmithsonian's National Zoo and Conservation Biology Institute
Animal Diversity Web (University of Michigan Museum of Zoology)
Reptiles of Ecuador (Arteaga 2024, in Arteaga, Bustamante & Vieira, eds.; Fundación Khamai and Tropical Herping)
U.S. Geological Survey, Nonindigenous Aquatic Species Database
|
| Geographic range | Native to tropical lowland South America east of the Andes, in Venezuela, Colombia, Brazil, Ecuador, Peru, Bolivia, Paraguay, Guyana, Suriname and French Guiana (the Amazon and Orinoco basins, the Guianas, the Llanos and the Cerrado), and to Trinidad.Includes the northern clade described in 2024 as Eunectes akayima (Northern Green Anaconda), which the taxonomic authority provisionally treats as a synonym. Introduced: probably released or escaped pets in Florida; one was confirmed dead on a road in the Fakahatchee Strand area in 2004 and none has been confirmed there since, though another account describes small introduced populations. One account also lists Argentina. | Matches source · The Reptile Database (Uetz et al.; new species and updates by the Zoological Museum Hamburg), Naturalis Biodiversity Center institutional repository (record of Rivas et al. 2024, Diversity 16: 127), Reptiles of Ecuador (Arteaga 2024, in Arteaga, Bustamante & Vieira, eds.; Fundación Khamai and Tropical Herping), Smithsonian's National Zoo and Conservation Biology Institute, U.S. Geological Survey, Nonindigenous Aquatic Species Database, Animal Diversity Web (University of Michigan Museum of Zoology) — how we knowThe Reptile Database (Uetz et al.; new species and updates by the Zoological Museum Hamburg)
Naturalis Biodiversity Center institutional repository (record of Rivas et al. 2024, Diversity 16: 127)
Reptiles of Ecuador (Arteaga 2024, in Arteaga, Bustamante & Vieira, eds.; Fundación Khamai and Tropical Herping)
Smithsonian's National Zoo and Conservation Biology Institute
U.S. Geological Survey, Nonindigenous Aquatic Species Database
Animal Diversity Web (University of Michigan Museum of Zoology)
|
| Habitat | Semi-aquatic in tropical fresh waters: swamps, marshes, slow rivers and streams, lagoons, flooded forests and seasonally flooded savannas and grasslands. Prefers shallow, slow-moving water with medium to dense aquatic vegetation, spending most of its time in or beside water.Found in both rainforest and savanna regions. One account puts about 86% of its time in the water and 14% at the water's edge, with an apparent preference for water less than 50 cm deep; another says it also uses deep, turbid and clear waters of lakes and rivers. On land it is found in thick vegetation, often in trees. | Matches source · Reptiles of Ecuador (Arteaga 2024, in Arteaga, Bustamante & Vieira, eds.; Fundación Khamai and Tropical Herping), Smithsonian's National Zoo and Conservation Biology Institute, Animal Diversity Web (University of Michigan Museum of Zoology), U.S. Geological Survey, Nonindigenous Aquatic Species Database — how we knowReptiles of Ecuador (Arteaga 2024, in Arteaga, Bustamante & Vieira, eds.; Fundación Khamai and Tropical Herping)
Smithsonian's National Zoo and Conservation Biology Institute
Animal Diversity Web (University of Michigan Museum of Zoology)
U.S. Geological Survey, Nonindigenous Aquatic Species Database
|
| Diet | An opportunistic predator of any vertebrate it can kill and swallow: fish, amphibians, reptiles, birds and mammals. It ambushes from the water and kills by constriction. Juveniles eat mainly birds; large adults take capybaras, deer, peccaries, tapirs, caimans, sheep and calves.It typically waits submerged, with only the eyes and nostrils above the surface, for animals that come to drink at the water's edge, and holds prey in its jaws while coiling around and constricting it. Juveniles also take fish and small mammals. Large prey usually weigh 14% to 50% of the snake's own mass. Some also eat carrion and other anacondas; females sometimes eat males. With a slow metabolism, it may go weeks or months without eating after a meal. | Matches source · Animal Diversity Web (University of Michigan Museum of Zoology), Reptiles of Ecuador (Arteaga 2024, in Arteaga, Bustamante & Vieira, eds.; Fundación Khamai and Tropical Herping), Smithsonian's National Zoo and Conservation Biology Institute, U.S. Geological Survey, Nonindigenous Aquatic Species Database, The Reptile Database (Uetz et al.; new species and updates by the Zoological Museum Hamburg) — how we knowAnimal Diversity Web (University of Michigan Museum of Zoology)
Reptiles of Ecuador (Arteaga 2024, in Arteaga, Bustamante & Vieira, eds.; Fundación Khamai and Tropical Herping)
Smithsonian's National Zoo and Conservation Biology Institute
U.S. Geological Survey, Nonindigenous Aquatic Species Database
The Reptile Database (Uetz et al.; new species and updates by the Zoological Museum Hamburg)
|
| Body size | Females are much larger than males. Maximum length is given as 6.6 m (females) and 3.39 m (males) by one account, 8 m for large females by another and 9 m by a third; averages of 3 m (males) and 6 m (females) are also given. Reports of 10–12 m are unconfirmed or disputed.sources disagreeA 7-year field study in the Venezuelan llanos found both the expected and the recorded maximum sizes well below the maxima reported in the literature. The 6.6 m and 3.39 m figures are snout-to-tail-tip maxima (a male snout-vent length of 3.31 m is also given); another account says adults can exceed 25 feet. | Sources disagree · Reptiles of Ecuador (Arteaga 2024, in Arteaga, Bustamante & Vieira, eds.; Fundación Khamai and Tropical Herping), U.S. Geological Survey, Nonindigenous Aquatic Species Database, Smithsonian's National Zoo and Conservation Biology Institute, Animal Diversity Web (University of Michigan Museum of Zoology), University of Tennessee, Knoxville Libraries, TRACE repository (record of Rivas 2000, PhD dissertation) — how we knowWhat each reading says
Maximum length disagrees: one account gives 6.6 m for females and 3.39 m for males and calls an 11.4 m report unconfirmed; another says large females reach 8 m (26 ft); a third gives up to 9 m (30 feet); a fourth cites records of 10 to 12 m whose actual maximal size is much disputed. Reptiles of Ecuador (Arteaga 2024, in Arteaga, Bustamante & Vieira, eds.; Fundación Khamai and Tropical Herping)
U.S. Geological Survey, Nonindigenous Aquatic Species Database
Smithsonian's National Zoo and Conservation Biology Institute
Animal Diversity Web (University of Michigan Museum of Zoology)
University of Tennessee, Knoxville Libraries, TRACE repository (record of Rivas 2000, PhD dissertation)
|
| Body mass | Much heavier for its length than other large constrictors. Maximum mass is given as 104.4 kg by one account and as 250 kg (550 pounds) by two others; a reported 227 kg is unconfirmed. Newborns average 200 g, about 1% of their mother's mass.sources disagreeOne account calls it clearly the heaviest snake; another says that, with weight and length both considered, it is the largest snake in the world. Figures are not split by sex, but females have a much larger mass than males. One 250 kg figure comes from records of 10 to 12 m snakes whose maximal size that account calls much disputed. | Sources disagree · Reptiles of Ecuador (Arteaga 2024, in Arteaga, Bustamante & Vieira, eds.; Fundación Khamai and Tropical Herping), Smithsonian's National Zoo and Conservation Biology Institute, Animal Diversity Web (University of Michigan Museum of Zoology), U.S. Geological Survey, Nonindigenous Aquatic Species Database — how we knowWhat each reading says
Maximum mass disagrees: one account gives up to 104.4 kg and calls a reported 227 kg unconfirmed, while two others give 250 kg (550 pounds), one of them from disputed records. Reptiles of Ecuador (Arteaga 2024, in Arteaga, Bustamante & Vieira, eds.; Fundación Khamai and Tropical Herping)
Smithsonian's National Zoo and Conservation Biology Institute
Animal Diversity Web (University of Michigan Museum of Zoology)
U.S. Geological Survey, Nonindigenous Aquatic Species Database
|
| Lifespan | Wild: about 10 years on average; one wild snake recaptured after 13 years was estimated to be 20 years old. Captivity: up to 31.8 years (maximum longevity record).Captive lifespans are also given as over 30 years and, in some reports, into the late 20s. The 31.8-year record is rated as based on a medium sample size with acceptable data quality. | Matches source · Smithsonian's National Zoo and Conservation Biology Institute, Animal Diversity Web (University of Michigan Museum of Zoology), Reptiles of Ecuador (Arteaga 2024, in Arteaga, Bustamante & Vieira, eds.; Fundación Khamai and Tropical Herping), Human Ageing Genomic Resources: AnAge, The Animal Ageing and Longevity Database (Build 15) — how we knowSmithsonian's National Zoo and Conservation Biology Institute
Animal Diversity Web (University of Michigan Museum of Zoology)
Reptiles of Ecuador (Arteaga 2024, in Arteaga, Bustamante & Vieira, eds.; Fundación Khamai and Tropical Herping)
Human Ageing Genomic Resources: AnAge, The Animal Ageing and Longevity Database (Build 15)
|
| Activity pattern | Appears to be active by day and night but avoids the hottest hours; one account says it is most active in the early evening. Where land floods seasonally, it must find water in the dry season or burrow into mud and stay dormant through the dry period; snakes near rivers are active all year.Individuals, especially breeding females, bask on sunny days on rocks, termite mounds, riverbanks or branches over the water. When inactive they hide in crevices, caves, among the roots of aquatic plants or deep in mud. | Matches source · Reptiles of Ecuador (Arteaga 2024, in Arteaga, Bustamante & Vieira, eds.; Fundación Khamai and Tropical Herping), Animal Diversity Web (University of Michigan Museum of Zoology), Smithsonian's National Zoo and Conservation Biology Institute — how we knowReptiles of Ecuador (Arteaga 2024, in Arteaga, Bustamante & Vieira, eds.; Fundación Khamai and Tropical Herping)
Animal Diversity Web (University of Michigan Museum of Zoology)
Smithsonian's National Zoo and Conservation Biology Institute
|
| Social structure | Mostly solitary, each keeping to its own hunting area outside the breeding season. Polyandrous: one female is courted by up to 13 males at once in a breeding aggregation. In the Venezuelan Llanos dry season, up to 34 may crowd around the last mud holes in a 10 × 20 m area.Male-to-male combat is rare. Larger males seem to select larger females, and larger females are courted by more males. | Matches source · Smithsonian's National Zoo and Conservation Biology Institute, Animal Diversity Web (University of Michigan Museum of Zoology), University of Tennessee, Knoxville Libraries, TRACE repository (record of Rivas 2000, PhD dissertation), Reptiles of Ecuador (Arteaga 2024, in Arteaga, Bustamante & Vieira, eds.; Fundación Khamai and Tropical Herping) — how we knowSmithsonian's National Zoo and Conservation Biology Institute
Animal Diversity Web (University of Michigan Museum of Zoology)
University of Tennessee, Knoxville Libraries, TRACE repository (record of Rivas 2000, PhD dissertation)
Reptiles of Ecuador (Arteaga 2024, in Arteaga, Bustamante & Vieira, eds.; Fundación Khamai and Tropical Herping)
|
| Reproduction | Mates in the dry season, a female often with several males. Young are born live in water after several months' gestation, usually 20–40 per litter by most accounts (up to 82). Matures at about 3–4 years; mates only every other year, by one account. Facultative parthenogenesis occurs.sources disagreeThe eggs hatch inside the mother. Litter size rises with female size, but larger females breed less often. Newborns measure 36–85 cm in total length. Females may eat males after mating and do not feed during gestation. | Sources disagree · Smithsonian's National Zoo and Conservation Biology Institute, Animal Diversity Web (University of Michigan Museum of Zoology), Reptiles of Ecuador (Arteaga 2024, in Arteaga, Bustamante & Vieira, eds.; Fundación Khamai and Tropical Herping), U.S. Geological Survey, Nonindigenous Aquatic Species Database, University of Tennessee, Knoxville Libraries, TRACE repository (record of Rivas 2000, PhD dissertation), The Reptile Database (Uetz et al.; new species and updates by the Zoological Museum Hamburg) — how we knowWhat each reading says
Accounts differ on the mating months (March to May, or April to May), gestation (7 months, 6–7 months, or 6 to 10 months), typical litter size (20–40, or 28 to 42) and how long breeding aggregations last (up to four weeks, or 2–46 days with an average of 18). Smithsonian's National Zoo and Conservation Biology Institute
Animal Diversity Web (University of Michigan Museum of Zoology)
Reptiles of Ecuador (Arteaga 2024, in Arteaga, Bustamante & Vieira, eds.; Fundación Khamai and Tropical Herping)
U.S. Geological Survey, Nonindigenous Aquatic Species Database
University of Tennessee, Knoxville Libraries, TRACE repository (record of Rivas 2000, PhD dissertation)
The Reptile Database (Uetz et al.; new species and updates by the Zoological Museum Hamburg)
|
| Human interaction | Attacks on people are rare, with predatory strikes reported but no well-documented deaths. People hunt anacondas, and some may kill them to protect livestock; live animals and skins are traded internationally under CITES Appendix II. The U.S. lists it as injurious wildlife.The bite is not venomous, but the curved teeth can tear flesh. One account attributes the rarity of attacks to low human population densities where the snakes live. Many people fear anacondas for their size. Illegal trade persists. In parts of Brazil and Peru, body parts are sold for ritual use and fat is used in folk medicine. Snakes found outside the native range are probably released or escaped pets. | Matches source · Smithsonian's National Zoo and Conservation Biology Institute, U.S. Geological Survey, Nonindigenous Aquatic Species Database, Reptiles of Ecuador (Arteaga 2024, in Arteaga, Bustamante & Vieira, eds.; Fundación Khamai and Tropical Herping), Animal Diversity Web (University of Michigan Museum of Zoology) — how we knowSmithsonian's National Zoo and Conservation Biology Institute
U.S. Geological Survey, Nonindigenous Aquatic Species Database
Reptiles of Ecuador (Arteaga 2024, in Arteaga, Bustamante & Vieira, eds.; Fundación Khamai and Tropical Herping)
Animal Diversity Web (University of Michigan Museum of Zoology)
|
| Conservation status | Least Concern (LC), global assessment, 2021 | Matches source · IUCN Red List of Threatened Species — how we knowIUCN Red List of Threatened Species
|
References for the facts above
- ReferenceThe Reptile Database (Uetz et al.; new species and updates by the Zoological Museum Hamburg)Supports: identity and synonymy (including the status of Eunectes akayima), range (country list), diet (large prey), reproduction (facultative parthenogenesis). Retrieved 2026-10-20.Limitations: Taxonomic record; its diagnosis and descriptive details are currently withheld from the public page. The distribution is a country list with no native or introduced tags. The query URL (species?genus=Eunectes&species=murinus) redirects to this record path.
- UniversitySmithsonian's National Zoo and Conservation Biology InstituteSupports: identification, range, habitat, diet, body-size, weight, lifespan, activity, social-structure, reproduction, human-interaction. Retrieved 2026-10-20.Limitations: Undated fact sheet without references. Its size figures (30 feet or 9 meters; 550 pounds or 250 kilograms) are stated as what the species can reach, without a source, and exceed the maxima other accounts give. Its statement that anacondas 'detach their jaw' was not used.
- UniversityAnimal Diversity Web (University of Michigan Museum of Zoology)Supports: identification, range, habitat, diet, body-size, weight, lifespan, activity, social-structure, reproduction, human-interaction. Retrieved 2026-10-20.Limitations: Student-written account (Milord 2012, last updated 2012-08-07). It lists 'the Bolivarian Republic of Argentina' among range countries, gives average lengths (3 m for males, 6 m for females) without sample or method, and its captive-lifespan fields list three differing averages (29.0, 8.0 and 13.9 years); those averages were not used.
- ReferenceReptiles of Ecuador (Arteaga 2024, in Arteaga, Bustamante & Vieira, eds.; Fundación Khamai and Tropical Herping)Supports: identification, range, habitat, diet, body-size, weight, lifespan, activity, social-structure, reproduction, human-interaction. Retrieved 2026-10-20.Limitations: Written for an Ecuador book but summarizes the species range-wide with numbered references; last updated 14 February 2024, before the Eunectes akayima description, so it does not address that split. Its male maximum gives both 3.39 m total length and 3.31 m snout-vent length; used as stated.
- GovernmentU.S. Geological Survey, Nonindigenous Aquatic Species DatabaseSupports: identification, range (native and introduced), habitat, diet, body-size, weight, reproduction, human-interaction. Retrieved 2026-10-20.Limitations: Florida-focused nonindigenous-species profile (revision date 7/31/2023), marked preliminary or provisional. Its size statements ('up to 26 ft (8m)' for large females; adults 'over 25 feet') are not tied to measured specimens on the page.
- UniversityUniversity of Tennessee, Knoxville Libraries, TRACE repository (record of Rivas 2000, PhD dissertation)Supports: body-size (field maxima versus literature maxima; sexual size dimorphism), social-structure and reproduction (breeding aggregations, female size and output). Retrieved 2026-10-20.Limitations: Abstract only; the dissertation PDF was not read, so its measured sizes are not available here. Field data come from the Venezuelan llanos.
- UniversityNaturalis Biodiversity Center institutional repository (record of Rivas et al. 2024, Diversity 16: 127)Supports: range (the 2024 proposal to split a Northern Green Anaconda, Eunectes akayima, from E. murinus). Retrieved 2026-10-20.Limitations: Abstract only; the split it proposes is not accepted by the Reptile Database, which treats E. akayima as a synonym of E. murinus.
- ReferenceHuman Ageing Genomic Resources: AnAge, The Animal Ageing and Longevity Database (Build 15)Supports: lifespan (captive maximum). Retrieved 2026-10-20.Limitations: The 31.8-year captive maximum cites a secondary web page (ref. 451, 'Frank & Kate's Web Page'); sample size Medium, data quality Acceptable. Its female maturity (912 days) and 'adult weight' (97,500 g) were not used.
- ReferenceIUCN Red List of Threatened SpeciesSupports: The global Red List category and the year of the assessment. Retrieved 2026-10-20.Limitations: Read from the Red List export IUCN publishes to GBIF; iucnredlist.org itself does not answer automated reads. Categories are reassessed over time.
Frequently Asked Questions — Green Anaconda
How big do green anacondas get?
Females are far larger than males. One account gives maximums of 6.6 m for females and 3.39 m for males; others give up to 8 m or 9 m. Reports of 10–12 m are unconfirmed or disputed, and a seven-year field study found the largest snakes well below the maxima in the literature.
Is the green anaconda venomous?
No. It kills by constriction. Its bite is not venomous, though its curved teeth can tear flesh.
Are green anacondas dangerous to people?
Attacks are rare: there are accounts of predatory strikes on people but no well-documented deaths.
What do green anacondas eat?
Any vertebrate they can kill and swallow — fish, amphibians, reptiles, birds and mammals. Young snakes eat mostly birds; large adults take capybaras, deer, peccaries, tapirs and caimans.
Sources and further reading
Authoritative wildlife references used for general educational context. Conservation status should always be verified against current IUCN Red List data. External links open in a new tab.
- ReferenceThe Reptile Database (Uetz et al.; new species and updates by the Zoological Museum Hamburg) — Eunectes murinus taxonomic record — identity and synonymy (including the status of Eunectes akayima), range (country list), diet (large prey), reproduction (facultative parthenogenesis)
- UniversitySmithsonian's National Zoo and Conservation Biology Institute — Green anaconda species account — identification, range, habitat, diet, body-size, weight, lifespan, activity, social-structure, reproduction, human-interaction
- UniversityAnimal Diversity Web (University of Michigan Museum of Zoology) — Eunectes murinus (green anaconda) species account — identification, range, habitat, diet, body-size, weight, lifespan, activity, social-structure, reproduction, human-interaction
- ReferenceReptiles of Ecuador (Arteaga 2024, in Arteaga, Bustamante & Vieira, eds.; Fundación Khamai and Tropical Herping) — Eunectes murinus, Reptiles of Ecuador — identification, range, habitat, diet, body-size, weight, lifespan, activity, social-structure, reproduction, human-interaction
- GovernmentU.S. Geological Survey, Nonindigenous Aquatic Species Database — Green anaconda, Nonindigenous Aquatic Species fact sheet — identification, range (native and introduced), habitat, diet, body-size, weight, reproduction, human-interaction
- UniversityUniversity of Tennessee, Knoxville Libraries, TRACE repository (record of Rivas 2000, PhD dissertation) — Rivas 2000, anaconda natural history (dissertation abstract) — body-size (field maxima versus literature maxima; sexual size dimorphism), social-structure and reproduction (breeding aggregations, female size and output)
- UniversityNaturalis Biodiversity Center institutional repository (record of Rivas et al. 2024, Diversity 16: 127) — Rivas et al. 2024, Eunectes akayima (abstract) — range (the 2024 proposal to split a Northern Green Anaconda, Eunectes akayima, from E. murinus)
- ReferenceHuman Ageing Genomic Resources: AnAge, The Animal Ageing and Longevity Database (Build 15) — Eunectes murinus longevity entry — lifespan (captive maximum)
- ReferenceIUCN Red List — Eunectes murinus assessment — The global Red List category and the year of the assessment