Reptilia · Squamata
Thamnophis foxiRossman & Blaney, 1968
Fox's Mountain Meadow Snake
No photograph of this species exists under a license anyone may reuse. It gets the same page regardless.
A ground-dwelling, active by day or night, meat-eating snake from the Nearctic region, reaching 454 mm nose to tail.
Once published as Adelophis foxi — those names reach this page.
Reptilia › Squamata › Colubridae › Thamnophis
- Grows to
- 454mm
- greatest recorded
- Eats
- Carnivorous
- Active
- Cathemeral
- Lives
- Terrestrial
Longer than only 28% 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
36 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
- Data Deficient
- Status assessed · the year the Red List last looked
- 2007
The animal itself
- Limbs
- None
- Pupil
- Round
- Venomous
- Yes
- Fangs
- At the back of the mouth
- Body temperature when active · measured in the wild
- 18.66°C66 °F
- Body temp in the wild · mean, when active
- 9–35°C48–95 °F
mean body temperature of active individuals in nature
body temperature of active animals in nature
Size
- Length snout to vent · greatest recorded
- 352.5mm14 in
- Length snout to vent · adult female mean
- 333mm13 in
- Length nose to tail · greatest recorded
- 454mm18 in
- Female length · mean, nose to tail
- 428.7mm17 in
- Hatchling length · snout to vent
- 120.3mm4.75 in
- Hatchling length · nose to tail
- 155mm6 in
- Body mass · greatestcomputed
- 21.49g0.76 oz
430 mm total length (Feldman et al. 2016), Rossman and Blaney 1968 (max 454 mm TL, 3 females 413-454, mean 428.7 mm, SVL 318-352.5, mean 333 mm, neonates 117.5-123 mm SVL, 150-160 TL)
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
- Cathemeral
- Where it lives
- Terrestrial
- Biome
- Tropical & Subtropical Coniferous Forests
- Region
- Nearctic
- Mainland or island
- Mainland
- Elevation · above sea level
- 2580m
- Range size
- 10km²
worms (Deepak et al. 2022), probbaly earthworms (Rossman and Blaney 1968)
v
Hernandez-Salinas et al. 2023
"surficial (terrestrial, non-scansorial)" (Gearty et al. 2021)/ burrowing (Deepak et al. 2022), terrestrial (Rossman and Blaney 1968)
8600 ft (Rossman and Blaney 1968)
Breeding
- Reproduction
- Viviparous
- Average clutch
- 3
- Eggs or young per clutch
- 2–4eggs
- Mean clutch
- 3eggs
Feldman et al. 2015, Deepak et al. 2022
midpoint of the reported range — Meiri, 2024, Glob. Ecol. Biogeogr., 33:e13812
2-4 (n=2, Rossman and Blaney 1968)
Naming and history
- Suborder
- Serpentes
- Infraorder
- Alethinophidia
- Subspecies
- No
- Described by
- Rossman & Blaney
- Moved to another genus · since it was first described
- No
- Described in
- 1968
- Type locality
- Mexico
Keeping one
18 in × 9 in × 13.5 in(45 × 23 × 34 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 18 in (454 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 66 °F (18.7 °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.
3kJ per day
Worked out for an animal of 21 g, the heaviest recorded for Fox's Mountain Meadow 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 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
- — 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
- — 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
- — Colour on the back
- — Pattern on the back
- — Sex decided by
- — Population trend
- — Red List criteria
- — Active season · shortest recorded
- — Active season · longest recorded
- — Density · lowest recorded
- — Density · highest recorded
- — Home range · largest recorded
- — Habitat
- — 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). Thamnophis foxi. Retrieved 2026-09-08, from https://www.allanglescreatures.com/species/thamnophis-foxi
@misc{thamnophis_foxi_2026,
title = {Thamnophis foxi},
author = {{The Reptile & Amphibian Encyclopedia}},
year = {2026},
url = {https://www.allanglescreatures.com/species/thamnophis-foxi}
}Sources
- Meiri, S. (2024). SquamBase — a database of squamate (Reptilia: Squamata) traits. Global Ecology and Biogeography. Public domain (CC0).
- Moura, M. R. et al. TetrapodTraits: a database of 33,281 tetrapod species. Used under CC BY 4.0. Observed values only; this encyclopedia does not publish its imputed predictions.
- Catalogue of Life (dataset 3LR), used under CC BY.
- Oskyrko, O. et al. (2024). ReptTraits: a comprehensive dataset of ecological traits in reptiles. Scientific Data. Used under CC BY 4.0.