Reptilia · Squamata
Ctenosaura bakeriStejneger, 1901
Baker's Spinytail Iguana
Photograph by Court Harding, CC BY, via iNaturalist
A tree-dwelling, day-active, plant-eating lizard from the Neotropic region, reaching 315 mm snout to vent.
Also called Utila Spiny-tailed Iguana.
Reptilia › Squamata › Iguanidae › Ctenosaura
- Grows to
- 315mm
- greatest recorded
- Eats
- Herbivorous
- Active
- Diurnal
- Lives up to
- 13.8years
Longer than only 44% 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
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
- Critically Endangered
- Status assessed · the year the Red List last looked
- 2018
- Population trend
- Decreasing
- Red List criteria
- B1ab(i,ii,iii,v)
The animal itself
- Limbs
- Four legs
- Venomous
- No
- Fangs
- None
- Longest recorded life
- 13.8years
De Magalhaes & Costa 2009, Slavens and Slavens 1999: 13 and 9 months
Size
- Length snout to vent · greatest recorded
- 315mm12.5 in
- Length snout to vent · adult female mean
- 192.6mm7.5 in
- Largest female · snout to vent
- 192.6mm7.5 in
- Hatchling length · snout to vent
- 57.5mm2.25 in
- Body mass · greatestcomputed
- 1339.6g3 lb
- Body mass · a typical adult
- 399.4g14.1 oz
- Body mass · adult female, meanmeasured
- 362.9g12.8 oz
max 315 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
- Active
- Diurnal
- Where it lives
- Arboreal
- Habitat
- Forest, Grassland
- Biome
- Tropical & Subtropical Moist Broadleaf Forests
- Region
- Neotropic
- Mainland or island
- Found only on islands
- Highest it lives · above sea level
- 30m
- Range size
- 42.1km²
- Density
- 20–114per hectare
"Ctenosaura bakeri is primarily herbivorous, eating flowers, leaves, stems, and fruit, but they will opportunistically eat smaller animals, eggs, and arthropods that inhabit the mangroves.[2][7] It has been observed eating smaller green iguanas (Iguana iguana) and geckos such as Hemidactylus frenatus." (Wikipedia), about 95% plants (McCranie 2018: "feed predominantly on mangrove parts (69%; leaves, flowers, and fruits), with crabs (4.4%) and insects and spiders (0.8%) also regularly consumed. Adult C. bakeri are normally herbivorous, but also feed on invertebrates throughout its life, but with a clear ontogenetic shift in the amount of invertebrates taken", bees (Maryon et al. 2021)
e.g., Maryon et al. 2021
Arboreal / mangrove specialist (Gutsche 2005)
near sea level (McCranie 2018), 6 (Maryon et al. 2021)
Breeding
- Reproduction
- Oviparous
- Average clutch
- 9.8eggs
- Eggs or young per clutch
- 5–19eggs
- Mean clutch
- 9.8eggs
mean 9.8 (Pasachnik 2013), 6-16 in the wild up to 19 in captivity (McCranie 2018), 5-19 (Langner et al. 2022)
Naming and history
- Suborder
- Sauria
- Infraorder
- Pleurodonta
- Subspecies
- No
- Described by
- Stejneger
- Moved to another genus · since it was first described
- No
- Described in
- 1901
- Type locality
- Honduras
Keeping one
Baker's Spinytail Iguana is assessed as Critically Endangered on the IUCN Red List. Species at risk in the wild are often covered by CITES and by national law, which decide what may be bought, sold, moved across a border or kept at all — and captive-bred and wild-caught animals are usually treated differently. Check the rules where you are before acquiring one. Nothing below is a judgement about keeping this species; it is what a published welfare standard says about space, and what the animal itself was measured doing.
4 ft 2 in × 2 ft 7 in × 4 ft 2 in(126 × 79 × 126 cm)
Minimum length × width × height, for one animal. Bigger is always better.
The standard sizes climbing species at 4 × 2.5 × 4 times snout-vent length.
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 snout-vent length of 12.5 in (315 mm), at 4 × 2.5 × 4 times it, following the German federal welfare standard — how this is worked out.
No preferred body temperature has been recorded for Baker's Spinytail Iguana. Rather than repeat a number from a care sheet, this page leaves it out.
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.
118kJ per day
Worked out for an animal of 1,340 g, the heaviest recorded for Baker's Spinytail 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 · 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
- — 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
- — Body temp in the wild · lowest mean recorded
- — Body temp in the wild · highest mean recorded
- — Colour on the back
- — Pattern on the back
- — Pupil
- — Sex decided by
- — Active season · shortest recorded
- — Active season · longest 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 bakeri. Retrieved 2026-09-08, from https://www.allanglescreatures.com/species/ctenosaura-bakeri
@misc{ctenosaura_bakeri_2026,
title = {Ctenosaura bakeri},
author = {{The Reptile & Amphibian Encyclopedia}},
year = {2026},
url = {https://www.allanglescreatures.com/species/ctenosaura-bakeri}
}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.