Opheodrys vernalisHarlan, 1827

Smooth Green Snake

Photograph by Dustin Snider, CC BY, via iNaturalist

A tree-dwelling, day-active, meat-eating snake from the Nearctic region, reaching 810 mm nose to tail.

Reptilia › Squamata › Colubridae › Opheodrys

Grows to: 810mm; greatest recorded
Eats: Carnivorous
Active: Diurnal
Lives up to: 6.1years

Body length across Colubridae

Longer than 60% of all colubrid snakes anyone has measured.

60% of 2,008 species are smaller40% 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

38 sourced facts, each taken from a named scientific dataset. How to read these.

Cited from a dataset unless a row is marked otherwise.

Two of these figures disagree

Body mass (a typical adult) is given as 104, and Body mass (greatest) as 72.6 — but a typical adult cannot outweigh the heaviest one ever recorded. They come from different sources and both are shown exactly as those sources give them.

Standing in the world

Still living: Extant
Conservation status: Least Concern
Status assessed · the year the Red List last looked: 2007
Population trend: Stable

The animal itself

Limbs: None
Colour on the back: Green
Pattern on the back: Uniform
Pupil: Round
Venomous: No
Fangs: At the back of the mouth
Longest recorded life: 6.1years
Body temperature when active · measured in the wild: 25.6°C78 °F
Body temp in the wild · mean, when active: 25.6°C

Size

Length nose to tail · greatest recorded: 810mm2 ft 8 in
Hatchling length · snout to vent: 142.2mm5.5 in
Hatchling length · nose to tail: 115mm4.5 in
Body mass · greatestcomputeddisputed: 72.64g2.6 oz
Body mass · a typical adultdisputed: 104g3.7 oz

How it lives

Diet: Carnivorous
Active: Diurnal
Where it lives: Arboreal
Habitat: Grassland, Shrubland, Wetlands
Biome: Temperate Broadleaf & Mixed Forests
Region: Nearctic
Mainland or island: Mainland
Highest it lives · above sea level: 2900m
Range size: 1,818,528km²

Breeding

Reproduction: Oviparous
Average clutch: 7.5
Eggs or young per clutch: 2–13eggs
Mean clutch: 5.1–6eggs

Naming and history

Suborder: Serpentes
Infraorder: Alethinophidia
Subspecies: No
Described by: Harlan
Moved to another genus · since it was first described: Yes
Described in: 1827
Type locality: USA

Keeping one

24 in × 16 in × 4 ft(61 × 41 × 122 cm)

Minimum length × width × height, for one animal. Bigger is always better.

The standard sizes snakes as a fraction of total length: 0.75 × 0.5 × 1.5.

Lives in vegetation, so height and climbing structure matter more than floor space.

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 8 in (810 mm), at 0.75 × 0.5 × 1.5 times it, following the German federal welfare standard — how this is worked out.

Active animals measured in the wild averaged 78 °F (25.6 °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.

9kJ per day

Worked out for an animal of 73 g, the heaviest recorded for Smooth Green 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
— Largest juvenile · snout to vent
— Largest juvenile · shell length
— Egg length
— Egg width
— Body mass · adult female, mean
— Body mass at hatching
— Preferred body temperature · chosen in a laboratory gradient
— Eats arthropods
— Eats vertebrates
— Eats plant matter
— How it hunts
— 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
— 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
— Lowest it lives · above sea level

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). Opheodrys vernalis. Retrieved 2026-09-08, from https://www.allanglescreatures.com/species/opheodrys-vernalis

@misc{opheodrys_vernalis_2026,
  title  = {Opheodrys vernalis},
  author = {{The Reptile & Amphibian Encyclopedia}},
  year   = {2026},
  url    = {https://www.allanglescreatures.com/species/opheodrys-vernalis}
}

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.
AnAge, Human Ageing Genomic Resources (de Magalhães et al.), used under CC BY 3.0.