Reptilia · Squamata
Ctenosaura hemilophaCope, 1863
Baja California Spiny- tailed Iguana
Photograph by Nancy Overholtz, CC BY-SA, via iNaturalist
A day-active, plant-eating lizard from the Nearctic region, reaching 400 mm snout to vent.
Reptilia › Squamata › Iguanidae › Ctenosaura
- Grows to
- 400mm
- greatest recorded
- Eats
- Herbivorous
- Active
- Diurnal
- Lives up to
- 13years
Longer than 58% of all iguanas 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 129 to 750 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
40 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 2,800, and Body mass (greatest) as 2,724.7 — 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
- 2020
The animal itself
- Limbs
- Four legs
- Venomous
- No
- Fangs
- None
- Longest recorded life
- 13years
- Body temperature when active · measured in the wild
- 37.1°C99 °F
- Body temp in the wild · mean, when active
- 37.1°C
Carey and Judge 2000, De Magalhaes & Costa 2009, Slavens and Slavens 1999: 9 and 7 months; Grismer 2002: "I have observed a colony of three to six lizards that has lived on the same rock pile for at least ten years." - Lee confirms (pers. com. 21.06.2014 at least one individual was there over the entire span ("At least one of the individuals was the same one because it had a deformed tail that was quite recognizable")
mean body temperature of active individuals in nature
body temperature of active animals in nature
Size
- Length snout to vent · greatest recorded
- 400mm15.5 in
- Length snout to vent · adult female mean
- 173mm6.75 in
- Largest female · snout to vent
- 173mm6.75 in
- Body mass · adult female, meanmeasured
- 728g1.6 lb
- Body mass · greatestcomputeddisputed
- 2724.7g6 lb
- Body mass · a typical adultdisputed
- 2800g6.2 lb
max 400 mm SVL (Feldman et al. 2016)
snout-vent length; the source column mixes this with straight carapace length
computed from length by a family-level allometric equation, not weighed
AnAge rates this record "acceptable"
How it lives
- Diet
- Herbivorous
- How it hunts
- Sit and wait
- Active
- Diurnal
- Where it lives
- Arboreal, saxicolous, terrestrial
- Habitat
- Desert, Rocky, Shrubland
- Biome
- Deserts & Xeric Shrublands
- Active season · months of the year
- 12months
- Region
- Nearctic
- Mainland or island
- Mainland
- Highest it lives · above sea level
- 1220m
- Range size
- 141,255km²
Herbivorous but will eat Arthropods and carrion (Grismer 2002 who considers C. conspiciosa distinct and says it is an omnivore, also Van Denburgh 1922), see also Banks and Farmer 1963, herbivore but eat rodents (Brennan and Holycross 2009), chiefly herbivore, also reptiles, crabs and other invertebrates (Stebbins and McGinnis 2018), mostly herbivorous, also carrion and arthropods (Heimes 2022)
Sit-and-wait (Cavalcanti et al. 2023)
e.g., Heimes 2022
Saxicolous and Arboreal and terrestrial (Rorabaugh 2008), arboreal & saxicolous (Stebbins and McGinnis 2018, Heimes 2022)
0-1220 (Stebbins and McGinnis 2018), 0-1000 (Heimes 2022)
Breeding
- Reproduction
- Oviparous
- Average clutch
- 24eggs
- Eggs or young per clutch
- 24eggs
- Mean clutch
- 24eggs
- Clutches in a year
- 1per year
- Clutches a year
- 1per year
- First breeds at
- 36months
13 follicles but not suere if all will mature (Goldberg and Beaman 2005), 24 (Van Wilgen and Richardson 2012)
Naming and history
- Suborder
- Sauria
- Infraorder
- Pleurodonta
- Subspecies
- No
- Described by
- Cope
- Moved to another genus · since it was first described
- Yes
- Described in
- 1863
- Type locality
- Mexico
Keeping one
5 ft 3 in × 5 ft 3 in × 5 ft 3 in(160 × 160 × 160 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 15.5 in (400 mm), at 4 × 4 × 4 times it, following the German federal welfare standard — how this is worked out.
Active animals measured in the wild averaged 99 °F (37.1 °C).
Mean body temperature of active individuals measured in nature. A measurement of the animal, not a setting for a thermostat.
Feeding
Prey size does not apply. A herbivore's diet is judged on fibre, on the ratio of calcium to phosphorus, and on avoiding plants high in oxalates.
The animal does not take prey items. This is established practice, not a measurement.
222kJ per day
Worked out for an animal of 2,725 g, the heaviest recorded for Baja California Spiny- tailed Iguana — 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 · snout to vent
- — Hatchling length · nose to tail
- — Largest juvenile · snout to vent
- — Largest juvenile · shell length
- — Egg length
- — Egg width
- — Body mass at hatching
- — Preferred body temperature · chosen in a laboratory gradient
- — Eats arthropods
- — Eats vertebrates
- — Eats plant matter
- — How the young develop
- — Gestation or incubation
- — 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
- — Population trend
- — Red List criteria
- — Density · lowest recorded
- — Density · highest recorded
- — Home range · largest recorded
- — Active in
- — Lowest it lives · above sea level
Others in Iguanidae
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). Ctenosaura hemilopha. Retrieved 2026-09-08, from https://www.allanglescreatures.com/species/ctenosaura-hemilopha
@misc{ctenosaura_hemilopha_2026,
title = {Ctenosaura hemilopha},
author = {{The Reptile & Amphibian Encyclopedia}},
year = {2026},
url = {https://www.allanglescreatures.com/species/ctenosaura-hemilopha}
}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.
- AnAge, Human Ageing Genomic Resources (de Magalhães et al.), used under CC BY 3.0.