Reptilia · Squamata
Phelsuma guentheriBoulenger, 1885
Round lsland Day Gecko
Photograph placed in the public domain, CC0, via iNaturalist
A tree-dwelling, active by day or night, omnivorous gecko from the Afrotropic region, reaching 147 mm snout to vent.
Reptilia › Squamata › Gekkonidae › Phelsuma
- Grows to
- 147mm
- greatest recorded
- Eats
- Omnivorous
- Active
- Cathemeral
- Lives up to
- 17.8years
Longer than 98% of all geckos 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 23 to 220 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.
Standing in the world
- Still living
- Extant
- Conservation status
- Vulnerable
- Status assessed · the year the Red List last looked
- 2018
- Population trend
- Increasing
- Red List criteria
- D2
The animal itself
- Limbs
- Four legs
- Venomous
- No
- Fangs
- None
- Longest recorded life
- 17.8years
De Magalhaes & Costa 2009: 17.8, Slavens and Slavens 1999: 17.75; Werner et al. 1993: 13 years, 7 months; Slavens and Slavens 1999: 13 and 2 months
Size
- Length snout to vent · greatest recorded
- 147mm5.75 in
- Length snout to vent · adult female mean
- 114.5mm4.5 in
- Largest female · snout to vent
- 115mm4.5 in
- Hatchling length · snout to vent
- 39.75mm1.5 in
- Largest juvenile · snout to vent
- 39.8mm1.5 in
- Body mass · greatestcomputed
- 55.2g1.9 oz
max 147 mm (Roesch et al. 2022a)
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
- Omnivorous
- Active
- Cathemeral
- Where it lives
- Arboreal
- Habitat
- Forest, Shrubland
- Biome
- Tropical & Subtropical Moist Broadleaf Forests
- Active season · months of the year
- 12months
- Region
- Afrotropic
- Mainland or island
- Found only on islands
- Elevation · above sea level
- 60m
- Range size
- 1873km²
- Density
- 1.2–9.9per hectare
Omnivorous: insects and fruit (Vinson and Vinson 1969) / leaves, fruit and arthropods (Bullock 1986) / 7% plants in adults, some reptiles, and birds, mostly invertbrates (Zuel 2009), "fruits, nectar, pollen, insects and other geckos" (Roesch et al. 2022a)
Diurnal (e.g., Bauer and Russell 1992)/ nocturnal (Uetz 2006) / basks by day, forages by night (Bullock 1986) / cathemeral (Zuel 2009, Roesch et al. 2022a)
(e.g., Bauer and Russell 1992, Zuel 2009), "cryptic and arboreal gecko" (Roesch et al. 2022a)
Breeding
- Reproduction
- Oviparous
- Sex decided by
- Temperature
- Average clutch
- 1.5eggs
- Eggs or young per clutch
- 1–2eggs
- Mean clutch
- 2eggs
1-2 Rosler 2005, 2 (Zuel 2009)
Naming and history
- Suborder
- Sauria
- Infraorder
- Gekkota
- Subspecies
- No
- Described by
- Boulenger
- Moved to another genus · since it was first described
- No
- Described in
- 1885
- Type locality
- Mauritius
Keeping one
Round lsland Day Gecko is assessed as Vulnerable 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.
23 in × 14.5 in × 23 in(59 × 37 × 59 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 5.75 in (147 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 Round lsland Day Gecko. Rather than repeat a number from a care sheet, this page leaves it out.
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.
7kJ per day
Worked out for an animal of 55 g, the heaviest recorded for Round lsland Day Gecko — 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
- — 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
- — Home range · largest recorded
- — Active in
Others in Gekkonidae
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). Phelsuma guentheri. Retrieved 2026-09-08, from https://www.allanglescreatures.com/species/phelsuma-guentheri
@misc{phelsuma_guentheri_2026,
title = {Phelsuma guentheri},
author = {{The Reptile & Amphibian Encyclopedia}},
year = {2026},
url = {https://www.allanglescreatures.com/species/phelsuma-guentheri}
}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.