Reptilia · Squamata
Ptyas dhumnadesCantor, 1842
Big-Eyed Ratsnake
Photograph by 雲一百香果, CC BY, via iNaturalist
A ground-dwelling, day-active, meat-eating snake from the Oriental region, reaching 263 cm nose to tail.
Also called Black-striped Rat Snake.
Reptilia › Squamata › Colubridae › Ptyas
- Grows to
- 2630mm
- greatest recorded
- Eats
- Carnivorous
- Active
- Diurnal
- Lives
- Terrestrial
Longer than 99% 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
37 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
- 2020
- Population trend
- Decreasing
The animal itself
- Limbs
- None
- Colour on the back
- Brown, Gray
- Pupil
- Round
- Fangs
- At the back of the mouth
Size
- Length snout to vent · adult female mean
- 1055mm3 ft 6 in
- Length nose to tail · greatest recorded
- 2630mm8 ft 8 in
- Female length · mean, nose to tail
- 1180mm3 ft 10 in
- Hatchling length · nose to tail
- 300mm12 in
- Body mass · greatestcomputed
- 1163.5g2.6 lb
- Body mass at hatchingmeasured
- 9.5g0.34 oz
2560 mm total length (Feldman et al. 2016), Dieckmann et al. 2014 (a 118 cm female laid 7 eggs, hatchlings "total lengths (measured with a ruler to the nearest cm) were all 30 cm, and body weights ranged from 9 to 10 g (mean ± SD = 9.8 ± 0.5)."), Wang et al. 2023 (female standard length [probably total length, unsure] 1040~1070 mm), Wang et al. 2023 (max total length 2630 mm)
snakes only in this source
computed from length by a family-level allometric equation, not weighed
How it lives
- Diet
- Carnivorous
- How it hunts
- Active foraging
- Active
- Diurnal
- Where it lives
- Terrestrial
- Habitat
- Forest, Grassland
- Biome
- Tropical & Subtropical Moist Broadleaf Forests
- Region
- Oriental
- Mainland or island
- Mainland
- Elevation · above sea level
- 151–2000m
- Range size
- 2,320,719km²
frogs, fishes, small mammals (Wang et al. 2023)
Wang et al. 2023
Diurnal snakes that actively forage for the rodents and frogs they prey upon' (Mehrtens 1987) (recorded by Anuj Shinde),
Breeding
- Reproduction
- Oviparous
- Average clutch
- 15eggs
- Eggs or young per clutch
- 5–17eggs
- Mean clutch
- 10.6eggs
- Egg length
- 45mm1.75 in
- Egg width
- 30mm1.25 in
Feldman et al. 2015
7-17 mean=10.6 s.d.=0.5 n=25 (Ji et al. 2000), Dieckmann et al. 2014 (a 118 cm female laid 7 eggs, 5-17 in the literature)
Naming and history
- Suborder
- Serpentes
- Infraorder
- Alethinophidia
- Subspecies
- No
- Described by
- Cantor
- Moved to another genus · since it was first described
- Yes
- Described in
- 1842
- Type locality
- China
Keeping one
8 ft 8 in × 4 ft 4 in × 6 ft 6 in(263 × 132 × 197 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 8 ft 8 in (2630 mm), at 1 × 0.5 × 0.75 times it, following the German federal welfare standard — how this is worked out.
No preferred body temperature has been recorded for Big-Eyed Ratsnake. Rather than repeat a number from a care sheet, this page leaves it out.
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.
104kJ per day
Worked out for an animal of 1,164 g, the heaviest recorded for Big-Eyed Ratsnake — 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 male mean
- — Length snout to vent · adult mean
- — 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 · snout to vent
- — Largest juvenile · snout to vent
- — Largest juvenile · shell length
- — Body mass · a typical adult
- — Body mass · adult female, mean
- — Longest recorded life
- — 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 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
- — Body temp in the wild · lowest mean recorded
- — Body temp in the wild · highest mean recorded
- — Pattern on the back
- — 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 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). Ptyas dhumnades. Retrieved 2026-09-08, from https://www.allanglescreatures.com/species/ptyas-dhumnades
@misc{ptyas_dhumnades_2026,
title = {Ptyas dhumnades},
author = {{The Reptile & Amphibian Encyclopedia}},
year = {2026},
url = {https://www.allanglescreatures.com/species/ptyas-dhumnades}
}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.