All Angles Creatures
Squamata · ColubridaeEntry 2,361 of 21,572
Thickhead Ground Snake, Atractus crassicaudatus

Reptilia · Squamata

Atractus crassicaudatusDuméril, Bibron, Duméril, 1854

Thickhead Ground Snake

Photograph placed in the public domain, CC0, via iNaturalist

A burrowing, meat-eating snake from the Neotropic region, reaching 420 mm nose to tail.

ReptiliaSquamataColubridaeAtractus

Grows to
420mm
greatest recorded
Eats
Carnivorous
Lives
Fossorial
Weighs up to
17.19g
greatest
Body length across Colubridae

Longer than only 22% of all colubrid snakes anyone has measured.

22% of 2,008 species are smaller78% larger
98 mmthe whole family, smallest to largest3,800 mm

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

25 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
2013
Population trend
Stable

The animal itself

Limbs
None
Pupil
Round
Fangs
At the back of the mouth

Size

Length nose to tail · greatest recorded
420mm16.5 in

snakes only in this source

Body mass · greatestcomputed
17.19g0.61 oz

computed from length by a family-level allometric equation, not weighed

How it lives

Dietcomputed
Carnivorous

no actual data but can be imputed as carnivorous like all snakes

Where it lives
Fossorial

Bars-Closel et al. 2017

Habitat
Grassland, Shrubland
Biome
Tropical & Subtropical Moist Broadleaf Forests
Region
Neotropic
Mainland or island
Mainland
Elevation · above sea level
2000–3200m

IUCN (2000 to 3200)

Range size
62,696km²

Breeding

Reproduction
Oviparous

Feldman et al. 2015

Naming and history

Suborder
Serpentes
Infraorder
Alethinophidia
Subspecies
No
Described by
Duméril, Bibron, Duméril
Moved to another genus · since it was first described
Yes
Described in
1854
Type locality
Colombia

Keeping one

16.5 in × 8.25 in × 12.5 in(42 × 21 × 32 cm)

Minimum length × width × height, for one animal. Bigger is always better. Substrate at least 8.25 in (21 cm) deep.

The standard sizes snakes as a fraction of total length: 1 × 0.5 × 0.75.

Burrows, so substrate deep enough to dig in matters as much as floor area.

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 16.5 in (420 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 Thickhead Ground Snake. 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.

2kJ per day

Worked out for an animal of 17 g, the heaviest recorded for Thickhead Ground 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 · 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 · snout to vent
  • Hatchling length · nose to tail
  • Largest juvenile · snout to vent
  • Largest juvenile · shell length
  • Egg length
  • Egg width
  • 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
  • Body temperature when active · measured in the wild
  • Eats arthropods
  • Eats vertebrates
  • Eats plant matter
  • How it hunts
  • Active
  • How the young develop
  • Gestation or incubation
  • Average clutch
  • Smallest clutch recorded
  • Largest clutch recorded
  • 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
  • Body temp in the wild · lowest mean recorded
  • Body temp in the wild · highest mean recorded
  • Colour on the back
  • 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). Atractus crassicaudatus. Retrieved 2026-09-08, from https://www.allanglescreatures.com/species/atractus-crassicaudatus

@misc{atractus_crassicaudatus_2026,
  title  = {Atractus crassicaudatus},
  author = {{The Reptile & Amphibian Encyclopedia}},
  year   = {2026},
  url    = {https://www.allanglescreatures.com/species/atractus-crassicaudatus}
}

Sources

  1. Meiri, S. (2024). SquamBase — a database of squamate (Reptilia: Squamata) traits. Global Ecology and Biogeography. Public domain (CC0).
  2. Catalogue of Life (dataset 3LR), used under CC BY.
  3. Oskyrko, O. et al. (2024). ReptTraits: a comprehensive dataset of ecological traits in reptiles. Scientific Data. Used under CC BY 4.0.