Reptilia · Squamata
Sceloporus zosteromusCope, 1863
Baja Spiny Lizard
Photograph by Daniela Gámez, CC BY, via iNaturalist
An active by day or night, meat-eating lizard from the Nearctic region, reaching 131 mm snout to vent.
Also called Central Baja Spiny Lizard, Mexican Desert Spiny Lizard, Monserrat Island Spiny Lizard.
Reptilia › Squamata › Phrynosomatidae › Sceloporus
- Grows to
- 131mm
- greatest recorded
- Eats
- Carnivorous
- Active
- Cathemeral
- Lives up to
- 6years
Longer than 95% of all species in Phrynosomatidae 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 47 to 175 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
37 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
- 2007
- Population trend
- Stable
The animal itself
- Limbs
- Four legs
- Venomous
- No
- Fangs
- None
- Longest recorded life
- 6years
- Preferred body temperature · chosen in a laboratory gradientmeasured
- 33.9°C
- Body temp in the wild · mean, when active
- 33.9°C
Myhrvold, Baldridge, Chan, Sivam, Freeman, and Ernest, 2015, Ecology, 96:3109-3109
body temperature of active animals in nature
Size
- Length snout to vent · greatest recorded
- 131mm5.25 in
- Length snout to vent · adult female mean
- 69.7mm2.75 in
- Largest female · snout to vent
- 67.7mm2.75 in
- Hatchling length · snout to vent
- 28.9mm1.25 in
- Largest juvenile · snout to vent
- 28.9mm1.25 in
- Body mass · greatestcomputed
- 65g2.3 oz
max 131 mm (e.g., Heimes 2022)
snout-vent length; the source column mixes this with straight carapace length
computed from length by a family-level allometric equation, not weighed
How it lives
- Diet
- Carnivorous
- Active
- Cathemeral
- Where it lives
- Arboreal, saxicolous, terrestrial
- Habitat
- Desert, Rocky, Shrubland
- Biome
- Deserts & Xeric Shrublands
- Active season · months of the year
- 6.5–12months
- Region
- Nearctic
- Mainland or island
- Mainland
- Highest it lives · above sea level
- 1700m
- Range size
- 126,799km²
Insects (see "Sources (general)")
Diurnal (e.g., Valdez-Villavicencio and Peralta-Garcia 2020)/also feeds at night (Flores-Villela and Rubio-Perez 2008), Grismer 2002 reports they are mainly diurnal, but "Tevis (1944) reports seeing a specimen east of El Rosario, foraging out in the open at night during early June. I have observed lizards out at night as well, but they did not seem to be foraging", "They are active during the day and occasionally you see them at night" (Lee Grismer, pers comm Oct 2019)
variable (e.g., Flores-Villela and Rubio-Perez 2008 / terrestrial, Van Denburgh 1922), saxicolous and arboreal (Heimes 2022)
coastal to 109, near sea level to 1700 (Heimes 2022)
Breeding
- Reproduction
- Oviparous
- Average clutch
- 6eggs
- Eggs or young per clutch
- 6–18eggs
- Mean clutch
- 6eggs
7-18 (Flores-Villela and Rubio-Perez 2008, Heimes 2022), mean 6 (Goldberg 2014)
Naming and history
- Suborder
- Sauria
- Infraorder
- Pleurodonta
- Subspecies
- Sceloporus zosteromus zosteromus COPE 1863 Sceloporus zosteromus monserratensis VAN DENBURGH & SLEVIN 1921 Sceloporus zosteromus rufidorsum YARROW 1882
- Described by
- Cope
- Moved to another genus · since it was first described
- No
- Described in
- 1863
- Type locality
- Mexico
Keeping one
20.5 in × 20.5 in × 20.5 in(52 × 52 × 52 cm)
Minimum length × width × height, for one animal. Bigger is always better.
The standard sizes ground species at 4 × 4 × 2.5 and climbing species at 4 × 2.5 × 4 times snout-vent length.
Recorded both on the ground and climbing, so this is the larger of the two rules in every dimension.
Lives on rock, so stable hard surfaces and basking ledges suit it.
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 snout-vent length of 5.25 in (131 mm), at 4 × 4 × 4 times it, following the German federal welfare standard — how this is worked out.
In a laboratory thermal gradient this species settled at 93 °F (33.9 °C).
Preferred body temperature, recorded in a laboratory gradient where the animal could choose freely. A measurement of the animal, not a setting for a thermostat.
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.
8kJ per day
Worked out for an animal of 65 g, the heaviest recorded for Baja Spiny Lizard — 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 · greatest recorded
- — Female length · mean, nose to tail
- — Length nose to tail · adult male mean
- — Length nose to tail · adult mean
- — Largest male · snout to vent
- — Largest female · shell length
- — Largest male · shell length
- — Hatchling length · nose to tail
- — Largest juvenile · shell length
- — Egg length
- — Egg width
- — Body mass · a typical adult
- — Body mass · adult female, mean
- — Body mass at hatching
- — Body temperature when active · measured in the wild
- — 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
- — Colour on the back
- — Pattern on the back
- — Pupil
- — Sex decided by
- — Red List criteria
- — Density · lowest recorded
- — Density · highest recorded
- — Home range · largest recorded
- — Active in
- — Lowest it lives · above sea level
Others in Phrynosomatidae
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). Sceloporus zosteromus. Retrieved 2026-09-08, from https://www.allanglescreatures.com/species/sceloporus-zosteromus
@misc{sceloporus_zosteromus_2026,
title = {Sceloporus zosteromus},
author = {{The Reptile & Amphibian Encyclopedia}},
year = {2026},
url = {https://www.allanglescreatures.com/species/sceloporus-zosteromus}
}Sources
- Meiri, S. (2024). SquamBase — a database of squamate (Reptilia: Squamata) traits. Global Ecology and Biogeography. Public domain (CC0).
- 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.
- 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.