Reptilia · Testudines
Terrapene triunguisAgassiz, 1857
Three-toed Box Turtle
Photograph placed in the public domain, CC0, via iNaturalist
An omnivorous turtle from the Nearctic region, reaching 18 cm across the shell.
Reptilia › Testudines › Emydidae › Terrapene
Longer than only 11% of all species in Emydidae 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 shell length here runs from 94 to 400 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
14 sourced facts, each taken from a named scientific dataset. How to read these.
Cited from a dataset unless a row is marked otherwise.
The animal itself
- Colour on the back
- Brown
- Pattern on the back
- Uniform
- Pupil
- Round
- Venomous
- No
- Fangs
- None
Size
- Shell length, front to back · greatest recorded
- 180mm7 in
straight carapace length, measured in a line rather than over the curve
How it lives
- Diet
- Omnivorous
- How it hunts
- Active foraging
- Region
- Nearctic
Invertebrates, plants
Breeding
- Reproduction
- Oviparous
Naming and history
- Subspecies
- No
- Described by
- Agassiz
- Moved to another genus · since it was first described
- Yes
- Described in
- 1857
Keeping one
2 ft 11 in × 17.5 in(90 × 45 cm)
Minimum floor length × width, for one animal. Bigger is always better. The standard sets no height for turtles and tortoises.
The standard sizes this genus at 5 times carapace length, with the width half the resulting length.
For a third and fourth turtle the standard asks for at least 10% more floor area each, and 20% more from the fifth onwards.
Water depth is set against the animal's carapace width rather than its length, so no figure is given here. Dry-country tortoises need no water area, only occasional bathing; tortoises from wetter regions need a water dish.
Swiss law reaches the same 8 × 4 of carapace length for land tortoises, arrived at separately from the German gutachten.
Gutachten über Mindestanforderungen an die Haltung von Reptilien (Sachverständigengruppe tierschutzgerechte Haltung von Terrarientieren), German Federal Ministry, 10 January 1997, section 5. The standard states these are recommendations rather than binding limits.
Swiss Tierschutzverordnung (TSchV), SR 455.1, Anhang 2, Tabelle 5 — legally binding minimum enclosure sizes, which give every land tortoise 8 × 4 body lengths for two animals.
From this animal’s own carapace length of 7 in (180 mm), at 5 times it — how this is worked out.
No preferred body temperature has been recorded for Three-toed Box Turtle. 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.
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.
- — Still living
- — 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
- — Length nose to tail · greatest recorded
- — 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 · greatest
- — 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
- — Active
- — Where it lives
- — 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
- — Body temp in the wild · lowest mean recorded
- — Body temp in the wild · highest mean recorded
- — Limbs
- — Sex decided by
- — Conservation status
- — Status assessed · the year the Red List last looked
- — Population trend
- — Red List criteria
- — Biome
- — Active season · shortest recorded
- — Active season · longest recorded
- — Density · lowest recorded
- — Density · highest recorded
- — Home range · largest recorded
- — Suborder
- — Infraorder
- — Type locality
- — Habitat
- — Active in
- — Mainland or island
- — Lowest it lives · above sea level
- — Highest it lives · above sea level
- — Range size
Others in Emydidae
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). Terrapene triunguis. Retrieved 2026-09-08, from https://www.allanglescreatures.com/species/terrapene-triunguis
@misc{terrapene_triunguis_2026,
title = {Terrapene triunguis},
author = {{The Reptile & Amphibian Encyclopedia}},
year = {2026},
url = {https://www.allanglescreatures.com/species/terrapene-triunguis}
}Sources
- 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.