
Reptilia · Squamata
Hebius vibakariBoie, 1826
Japanese Keelback
Photograph by W.CC, CC BY-SA, via Wikimedia Commons
A ground-dwelling, dawn-and-dusk, meat-eating snake from the Palearctic region, reaching 650 mm nose to tail.
Reptilia › Squamata › Colubridae › Hebius
- Grows to
- 650mm
- greatest recorded
- Eats
- Carnivorous
- Active
- Crepuscular
- Lives
- Terrestrial
Longer than only 48% of all colubrid snakes anyone has measured.
The bar is the rank itself: its length is the share of the family this animal exceeds. The chart below is the family’s real spread, on a logarithmic scale because body length here runs from 98 to 3,800 mm. The solid rule is this animal. Every bar is a count of real species, and nothing on this figure is estimated.
What is known
35 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
- 2016
The animal itself
- Limbs
- None
- Colour on the back
- Brown
- Pupil
- Round
- Fangs
- At the back of the mouth
- Body temperature when active · measured in the wild
- 24.8°C77 °F
- Body temp in the wild · mean, when active
- 17.5–33°C64–91 °F
mean body temperature of active individuals in nature
body temperature of active animals in nature
Size
- Length nose to tail · greatest recorded
- 650mm2 ft 2 in
- Hatchling length · snout to vent
- 155mm6 in
- Body mass · greatestcomputed
- 67.29g2.4 oz
snakes only in this source
650 mm total length (Feldman et al. 2016), max SVL 40 mm, tail 11 cm, hatchling body length 15-16 cm (Dunayev and Orlova 2023), Wang et al. 2023 (female standard length [probably total length, unsure] 441~458 mm)
computed from length by a family-level allometric equation, not weighed
How it lives
- Diet
- Carnivorous
- How it hunts
- Active foraging
- Active
- Crepuscular
- Where it lives
- Terrestrial
- Habitat
- Forest, Grassland
- Biome
- Temperate Broadleaf & Mixed Forests
- Region
- Palearctic
- Mainland or island
- Mainland
- Elevation · above sea level
- 60–90m
- Range size
- 1,229,460km²
earthworms, frogs, tadpoles, and loaches (Park et al. 2022), molluscs, insects, frogs (Dunayev and Orlova 2023)
Wang et al. 2023
"Although diurnal, it prefers cooler temperatures and is active mainly in the early mornings and evenings (Goris and Maeda 2004) (recorded by Anuj Shinde), hides during the day (Dunayev and Orlova 2023)
Deepak et al. 2022
62-84 (Park et al. 2022)
Breeding
- Reproduction
- Oviparous
- Sex decided by
- Genes, ZW/ZZ
- Average clutch
- 3eggs
- Eggs or young per clutch
- 2–6eggs
- Egg length
- 29.1mm1.25 in
- Egg width
- 11.7mm0.5 in
Feldman et al. 2015
2-6 (Dunayev and Orlova 2023)
Naming and history
- Suborder
- Serpentes
- Infraorder
- Alethinophidia
- Subspecies
- Hebius vibakari danjoensis TORIBA 1986 Hebius vibakari vibakari (BOIE 1826) Hebius vibakari ruthveni (VAN DENBURGH 1923)
- Described by
- Boie
- Moved to another genus · since it was first described
- Yes
- Described in
- 1826
- Type locality
- Japan
Keeping one
2 ft 2 in × 13 in × 19 in(65 × 33 × 49 cm)
Minimum length × width × height, for one animal. Bigger is always better.
The standard sizes snakes as a fraction of total length: 1 × 0.5 × 0.75.
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 total length of 2 ft 2 in (650 mm), at 1 × 0.5 × 0.75 times it, following the German federal welfare standard — how this is worked out.
Active animals measured in the wild averaged 77 °F (24.8 °C).
Mean body temperature of active individuals measured in nature. A measurement of the animal, not a setting for a thermostat.
Feeding
A prey item should be between the same width as the widest part of the snake's body and about 1.5 times that width.
Widely used across snake husbandry references. An alternative formulation gives prey at 10-15% of the snake's body mass. This is established practice, not a measurement.
8kJ per day
Worked out for an animal of 67 g, the heaviest recorded for Japanese Keelback — 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 · greatest recorded
- — 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 · snout to vent
- — Largest juvenile · shell length
- — Body mass · a typical adult
- — Body mass · adult female, mean
- — Body mass at hatching
- — Longest recorded life
- — Preferred body temperature · chosen in a laboratory gradient
- — Eats arthropods
- — Eats vertebrates
- — Eats plant matter
- — How the young develop
- — Gestation or incubation
- — Mean clutch · smallest reported
- — Mean clutch · largest reported
- — Clutches in a year
- — 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
- — Venomous
- — Pattern on the back
- — Population trend
- — 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 Colubridae
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). Hebius vibakari. Retrieved 2026-09-08, from https://www.allanglescreatures.com/species/hebius-vibakari
@misc{hebius_vibakari_2026,
title = {Hebius vibakari},
author = {{The Reptile & Amphibian Encyclopedia}},
year = {2026},
url = {https://www.allanglescreatures.com/species/hebius-vibakari}
}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.