Reptilia · Squamata
Agkistrodon russeolusGloyd, 1972
Mexican Moccasin
Photograph by Sebastián de Jesús Herrera Buenfil, CC BY, via iNaturalist
A ground-dwelling, nocturnal, meat-eating snake from the Neotropic region, reaching 105 cm nose to tail.
Also called Yucatecan Cantil.
Reptilia › Squamata › Viperidae › Agkistrodon
- Grows to
- 1050mm
- greatest recorded
- Eats
- Carnivorous
- Active
- Nocturnal
- Lives up to
- 19.11years
Longer than 69% of all vipers 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 280 to 3,900 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
32 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
The animal itself
- Limbs
- None
- Colour on the back
- Black, Brown
- Pattern on the back
- Banded
- Pupil
- Vertical slit
- Venomous
- Yes
- Fangs
- At the front of the mouth
- Longest recorded life
- 19.11years
Size
- Length snout to vent · greatest recorded
- 860mm2 ft 10 in
- Length nose to tail · greatest recorded
- 1050mm3 ft 5 in
- Female length · mean, nose to tail
- 782.9mm2 ft 7 in
- Hatchling length · snout to vent
- 213mm8.5 in
- Hatchling length · nose to tail
- 265mm10.5 in
- Body mass · greatestcomputed
- 422.8g14.9 oz
- Body mass · adult female, meanmeasured
- 318.3g11.2 oz
1050 mm total length (Feldman et al. 2016), "The SVL of A. russeolus ranged 213–860 mm (mean = 545.43 ± 158.325 mm), whereas TTL ranged 265–1050 mm (mean = 663.376 ± 190.674 mm)." (Ortiz-Medina et al. 2022, who seem to consider ~500 mm as the min SVL at maturity; From Table 2 female SVL is 510-820, means 563.93-743.75; total lengths 617-970, means 893.75-672.07 mm, mass 116.2-546, means 152.21-484.3g)
snakes only in this source
computed from length by a family-level allometric equation, not weighed
How it lives
- Diet
- Carnivorous
- How it hunts
- Ambush
- Active
- Nocturnal
- Where it lives
- Terrestrial
- Habitat
- Forest, Marine Coastal, Marine Intertidal, Shrubland, Wetlands
- Biome
- Tropical & Subtropical Dry Broadleaf Forests
- Region
- Neotropic
- Mainland or island
- Mainland
- Range size
- 65,549km²
mostly lizards and mammals, also frogs, snakes and birds (Ortiz-Medina et al. 2022)
obtained via noght-driving: Ortiz-Medina et al. 2022
obtained from roads, Ortiz-Medina et al. 2022
Breeding
- Reproduction
- Viviparous
Feldman et al. 2015
Naming and history
- Suborder
- Serpentes
- Infraorder
- Alethinophidia
- Subspecies
- No
- Described by
- Gloyd
- Moved to another genus · since it was first described
- No
- Described in
- 1972
- Type locality
- Mexico
Keeping one
3 ft 5 in × 20.5 in × 2 ft 7 in(105 × 53 × 79 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 3 ft 5 in (1050 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 Mexican Moccasin. 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.
42kJ per day
Worked out for an animal of 423 g, the heaviest recorded for Mexican Moccasin — 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 female mean
- — 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 at hatching
- — 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
- — 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
- — Sex decided by
- — Conservation status
- — Status assessed · the year the Red List last looked
- — Population trend
- — 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
- — Highest it lives · above sea level
Others in Viperidae
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). Agkistrodon russeolus. Retrieved 2026-09-08, from https://www.allanglescreatures.com/species/agkistrodon-russeolus
@misc{agkistrodon_russeolus_2026,
title = {Agkistrodon russeolus},
author = {{The Reptile & Amphibian Encyclopedia}},
year = {2026},
url = {https://www.allanglescreatures.com/species/agkistrodon-russeolus}
}Sources
- Meiri, S. (2024). SquamBase — a database of squamate (Reptilia: Squamata) traits. Global Ecology and Biogeography. Public domain (CC0).
- 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.