Reptilia · Squamata
Acrochordus javanicusHornstedt, 1787
Javan File Snake
Photograph by Ian Dugdale, CC BY, via iNaturalist
A water-living, nocturnal, meat-eating lizard from the Oriental region, reaching 290 cm nose to tail.
Also called Elephant Trunk Snake.
Reptilia › Squamata › Acrochordidae › Acrochordus
- Grows to
- 2900mm
- greatest recorded
- Eats
- Carnivorous
- Active
- Nocturnal
- Lives up to
- 20years
What is known
40 sourced facts, each taken from a named scientific dataset. How to read these.
Cited from a dataset unless a row is marked otherwise.
Standing in the world
- Still living
- Extant
- Conservation status
- Least Concern
- Status assessed · the year the Red List last looked
- 2011
- Population trend
- Stable
The animal itself
- Limbs
- None
- Colour on the back
- Brown
- Pattern on the back
- Banded
- Pupil
- Round
- Venomous
- No
- Fangs
- None
- Longest recorded life
- 20years
Stark et al. 2020 (20), Cox et al. 2012: more than 5 years and 9 months
Size
- Length snout to vent · greatest recorded
- 1550mm5 ft 1 in
- Length nose to tail · greatest recorded
- 2900mm9 ft 6 in
- Hatchling length · snout to vent
- 320mm12.5 in
- Largest juvenile · snout to vent
- 40mm1.5 in
- Body mass · greatestcomputed
- 830.1g1.8 lb
- Body mass at hatchingmeasured
- 42g1.5 oz
2900 mm total length (Feldman et al. 2016), Shine 1995 (SVL conservatively estimates at 850-1550 from Figure 1 in Shine et al. 1995, females considerably larger than males, fullterm embryos female means 236.4-259.9 SVL, males 249.4-286.5 mm, but 280-360 at birth in Table 1; min male SVL at adulthood 960 mm, but some larger males are immature, smallest mature female = 1140 mm, largest immature 1300 mm, neonate mass 42g from Bergmann 1958), Cox et al. 2012 (max 2.5 m)
snakes only in this source
computed from length by a family-level allometric equation, not weighed
How it lives
- Diet
- Carnivorous
- How it hunts
- Ambush
- Active
- Nocturnal
- Where it lives
- Aquatic
- Habitat
- Marine Neritic, Wetlands
- Biome
- Tropical & Subtropical Moist Broadleaf Forests
- Region
- Oriental
- Mainland or island
- Mainland
- Lowest it lives · above sea level
- 43m
- Highest it lives · above sea level
- 150m
- Range size
- 1,917,152km²
fish and aquatic snails (Shine et al. 1995), fish and eels (Cox et al. 2012)
Murphy et al. 2003
Cogger 2018, Murphy et al. 2003
IUCN (0 to 150)
Breeding
- Reproduction
- Viviparous
- Average clutch
- 17eggs
- Eggs or young per clutch
- 13–52eggs
- Mean clutch
- 26–29.3eggs
- Clutches in a year
- 1per year
Feldman et al. 2015
mean=26 (Murphy et al. 2003), Shine et al. 1995 (13-52 mean 29.3, n = 40), 25-50 (Cox et al. 2012)
Naming and history
- Suborder
- Serpentes
- Infraorder
- Alethinophidia
- Subspecies
- No
- Described by
- Hornstedt
- Moved to another genus · since it was first described
- No
- Described in
- 1787
- Type locality
- Indonesia
Keeping one
20 ft 4 in × 20 ft 4 in × 12 ft 9 in(620 × 620 × 388 cm)
Minimum length × width × height, for one animal. Bigger is always better.
The standard sizes ground-dwelling species at 4 × 4 × 2.5 times snout-vent length.
Spends time in water, so a water area is part of the enclosure rather than a dish.
Mindestanforderungen an die Haltung von Reptilien (Sachverständigengutachten), German Federal Ministry for Nutrition, Agriculture and Forestry, Animal Welfare Division, 10 January 1997. The standard states these floor areas are recommendations rather than binding limits.
From this animal’s own snout-vent length of 5 ft 1 in (1550 mm), at 4 × 4 × 2.5 times it, following the German federal welfare standard — how this is worked out.
No preferred body temperature has been recorded for Javan File Snake. Rather than repeat a number from a care sheet, this page leaves it out.
Feeding
A prey item should be no wider than the space between the animal's eyes.
Widely used across reptile husbandry references. The stated reason is that the gap approximates the width of the throat, so wider prey is associated with impaction. This is established practice, not a measurement.
77kJ per day
Worked out for an animal of 830 g, the heaviest recorded for Javan File Snake — so it is the top of the range, not a figure for a particular animal. Weigh yours and the number will be lower.
An upper estimate, not a feeding target, and not veterinary advice. The equation covers only what an animal burns staying alive, so a growing, gravid or recovering animal needs more — and it was measured on wild animals, which move far more than one in an enclosure. Body condition and a vet who knows the species are what a feeding decision should rest on. Where this comes from.
What nobody knows
These are not gaps in our research. No scientific dataset records them for this species — and saying so is information you cannot get from a reference that simply leaves a field out.
- — Length snout to vent · adult female mean
- — Length snout to vent · adult male mean
- — Length snout to vent · adult mean
- — Female length · mean, nose to tail
- — Length nose to tail · adult male mean
- — Length nose to tail · adult mean
- — Largest female · snout to vent
- — Largest male · snout to vent
- — Largest female · shell length
- — Largest male · shell length
- — Hatchling length · nose to tail
- — Largest juvenile · shell length
- — Egg length
- — Egg width
- — Body mass · a typical adult
- — Body mass · adult female, mean
- — Preferred body temperature · chosen in a laboratory gradient
- — Body temperature when active · measured in the wild
- — Eats arthropods
- — Eats vertebrates
- — Eats plant matter
- — How the young develop
- — Gestation or incubation
- — Clutches a year · fewest
- — Clutches a year · most
- — First breeds from · youngest recorded
- — First breeds by · oldest recorded
- — Hatchling length · smallest recorded
- — Hatchling length · largest recorded
- — Age at first breeding · female
- — Mature from · youngest recorded
- — Mature by · oldest recorded
- — Size at maturity · smallest recorded
- — Size at maturity · largest recorded
- — Body temp in the wild · lowest mean recorded
- — Body temp in the wild · highest mean recorded
- — Sex decided by
- — Red List criteria
- — Active season · shortest recorded
- — Active season · longest recorded
- — Density · lowest recorded
- — Density · highest recorded
- — Home range · largest recorded
- — Active in
Others in Acrochordidae
Take this data
Everything on this page is available as data under CC BY 4.0 — use it freely, credit it, no permission needed.
This species as JSON · the whole dataset
Cite this page
The Reptile & Amphibian Encyclopedia (2026). Acrochordus javanicus. Retrieved 2026-09-08, from https://www.allanglescreatures.com/species/acrochordus-javanicus
@misc{acrochordus_javanicus_2026,
title = {Acrochordus javanicus},
author = {{The Reptile & Amphibian Encyclopedia}},
year = {2026},
url = {https://www.allanglescreatures.com/species/acrochordus-javanicus}
}Sources
- Meiri, S. (2024). SquamBase — a database of squamate (Reptilia: Squamata) traits. Global Ecology and Biogeography. Public domain (CC0).
- Oskyrko, O. et al. (2024). ReptTraits: a comprehensive dataset of ecological traits in reptiles. Scientific Data. Used under CC BY 4.0.
- Catalogue of Life (dataset 3LR), used under CC BY.