Home / Reptiles / Lizards / Madagascar giant day gecko
Some federal rules applyMadagascar giant day gecko
Phelsuma grandis
Reptiles › Lizards (Lacertilia) › Gekkonidae (Geckos)
Phelsuma grandis is a diurnal arboreal species of day gecko.

Care at a glance
Species-specific values
Values researched for this exact species. Where they differ from the group guide below, follow these. Air, surface and water temperatures are listed separately, and each source is kept as published rather than averaged.
| Basking zone temperature | 95 °F Source does not specify surface versus air. | 241 |
| Day air temperature | 82–86 °F | 241 |
| Night air temperature | 75–82 °F | 241 |
| Relative humidity | 50–70 % | 241 |
| Adult total length | male max: 12 in; female typical: 10–11 in | 241 |
| Lifespan | 6–8 years Reported average range; exceptional records reach 20 years. | 241 |
| Diet | Varied appropriately sized insects and a nutritionally complete frugivorous-gecko formulation. | 241 |
Care guide
Day geckos
Applies to most species in this group. Habitat: Tropical islands and forests. Individual species can differ, so compare with the species numbers above and the linked sources.
Housing & setup
- Tall, planted enclosures with bamboo or broad leaves; UVB and a basking spot are needed.
- Very fast and delicate-skinned: watch, don't handle.
Climate & lighting
| Basking spot | 88–92°F |
| Warm side / daytime | 80–85°F |
| Cool side | 72–76°F |
| Humidity | 60–75% |
- UVB: Required.
Diet
- Phelsuma grandis can receive varied insects plus a nutritionally complete frugivorous-gecko food; nectar or plain fruit alone is not a complete formulation.
Health watch
- Skin tears easily if grabbed; MBD without UVB and calcium.
Understanding the animal
About this animal
About this animal
These geckos are part of the Phelsuma group, which consists of in excess of 70 species and subspecies. They are commonly referred to as the Madagascar giant day gecko, due to their large size.
Quoted from the Wikipedia article “Phelsuma grandis” (CC BY-SA 4.0) 174
In the wild
In the wild
Researched for this exact species, not its family. Good care copies these conditions.123
| Where it lives | Warm tropical and subtropical habitats in northern Madagascar. Uses vegetation and can occupy smooth vertical surfaces. |
| Ground it lives on | Arboreal; vegetation and vertical surfaces. |
| Climate | Warm, humid conditions reported throughout the year; measured wild temperature and relative-humidity ranges were not established. |
| Active | Diurnal. |
| Wild diet | Insects and other invertebrates, with fruit, berries, flowers and young plant material also reported. |
| Behavior to plan for | Adhesive toe structures permit climbing even on glass. Courtship and copulation can be aggressive. |
What this means for care
- Provide vertical climbing surfaces and foliage.
- Provide daylight and elevated basking opportunities.
- Secure tops and doors against glass-climbing escapes.
Native climate (measured)
Native climate (measured)
| Warm-season highs | about 85°F (up to 89°F in the hottest sampled areas) |
| Cool-season lows | about 63°F (down to 59°F in the coldest sampled areas) |
| Average temperature | 70–78°F across sampled records |
| Relative humidity | 75–78% on average (driest month about 74%) |
| Rainfall | about 1622 mm a year |
Measured at 84 wild occurrence records sampled against WorldClim 2.1 climate data (1970–2000 averages). Air conditions in the range are ecological context, not enclosure settings: microhabitats such as burrows, leaf litter or basking rocks can be cooler, warmer or more humid.
Profile
Profile
Researched for this exact species. Sources are listed under In the wild above.
History
Phelsuma grandis was described by Gray in 1870 and was formerly treated as the subspecies Phelsuma madagascariensis grandis. Raxworthy and colleagues elevated it to species status in 2007 after environmental niche modeling found significant differences, and the separation later received molecular support.
Keeper tips
- Design the enclosure around an arboreal rather than ground-dwelling animal.
- Provide opportunities for climbing and elevated positioning.
- Account for a diet that naturally includes invertebrates, very small vertebrates, and nectar.
- Adult animals may develop visible calcium-storage sacs on the neck.
Behaviors reported
- Active during the day.
- Lives arboreally.
Remarkable facts
- Adults reach about 9 to 11 inches in total length.
- Females are generally smaller than males.
- The body is usually bright green and may rarely be bluish green.
- A red stripe extends from the nostril to the eye.
- Young individuals often have more extensive red markings than adults, and many of those markings fade as they mature.
- Adults may possess neck sacs that store calcium.
From the sources
From the sources
Quoted from the matching sections of reputable sources for this exact species. Specialist databases are used first; Wikipedia (community-edited, CC BY-SA 4.0) only fills gaps. Other sources are short credited quotes.
| Overview | Phelsuma grandis is a diurnal arboreal species of day gecko. These geckos are part of the Phelsuma group, which consists of in excess of 70 species and subspecies. They are commonly referred to as the Madagascar giant day gecko, due to their large size. They are native to areas of tropical and subtropical forest in northern Madagascar, but have been introduced to several other subtropical locations outside their range. — Wikipedia (community-edited) |
| Where it lives | This species is widely distributed in northern and northwest Madagascar. There are a few recorded populations of this species also in Florida and Hawaii. — Wikipedia (community-edited) |
| Wild diet | These day geckos feed on various insects and other invertebrates, and occasionally have been recorded consuming small vertebrates. They also like to lick soft, sweet fruit, pollen and nectar. Studies show that P. grandis prefer nectars with a red or yellow coloring, and that trait is innate to all geckos. — Wikipedia (community-edited) |
| Behavior | Like most Phelsuma species, the males can be quite quarrelsome and territorial and will not accept other males in their neighborhood. They only allow females to enter their territory. In captivity, where the females cannot escape, the males can also sometimes seriously wound a female. — Wikipedia (community-edited) |
| Reproduction | Exhibits temperature‐dependent sex determination (TSD) fide Cornejo-Páramo et al. 2020 (and references therein). — The Reptile Database |
| Appearance and size | This lizard reaches a total length of 9–11″ (23–28cm), with females generally being smaller than males. The body colour is bright green or, rarely, bluish green. A red stripe extends from the nostril to the eye. — Wikipedia (community-edited) |
| History and naming | The specific epithet, grandis, is a Latin adjective, meaning ‘big’ or ‘large’, in reference to the larger body size of this new species compared to most congeners. — The Reptile Database |
Data and studies
The numbers
The numbers
Each bar is what one source reports. Where several sources weigh in, the dashed gold band marks their average.
Maximum recorded lifespan
Longest recorded lifespan reported by each database; typical lifespans are usually shorter.
Typical adult weight
Average adult body mass in each database (FishBase gives the maximum recorded weight).
Incubation
Veterinary & husbandry research
Veterinary & husbandry research
- Two new species of coccidia (Apicomplexa: Eimeriidae) from leaf-tailed geckos, Uroplatus spp. (Sauria: Gekkonidae) from Madagascar, including a new host of Eimeria brygooi Upton & Barnard, 1987 McAllister CT et al., Systematic parasitology 2016
Peer-reviewed papers that mention this species alongside captivity, zoos, veterinary care or aquaculture. Some cover several species or mention it only in passing, so check the abstract. 170
Sources for this sheet
- Myhrvold et al. (2015). An amniote life-history database. Ecology 96: 3109 Peer-reviewed researchPeer-reviewed compilation of life-history data for over 21,000 birds, mammals and reptiles.
- Species+ (UNEP-WCMC and the CITES Secretariat) Zoo, university or veterinaryThe official database of species listed under CITES.
- USFWS International Affairs: CITES Zoo, university or veterinaryFederal agency that issues CITES permits.
- Merck Veterinary Manual: Management and husbandry of reptiles Zoo, university or veterinaryThe Merck Veterinary Manual: a standard veterinary reference written and reviewed by veterinary specialists.
- Merck Veterinary Manual: Nutritional, metabolic and endocrine diseases of reptiles Zoo, university or veterinaryThe Merck Veterinary Manual: a standard veterinary reference written and reviewed by veterinary specialists.
- Reptiles Magazine: Giant day gecko care sheet Experienced keeper or breederAdded in the 2026 source-checked care-guide review.
- Clint's Reptiles (YouTube): Giant Day Gecko, The Best Pet Lizard? Expert educator & keeperClint Laidlaw, PhD in Biology Education and MS in Evolutionary Ecology; owner of Clint's Reptile Room and a longtime keeper. His "Best Pet?" series reviews each species' care in depth.
- The Reptile Database Peer-reviewed researchScientist-curated catalog of every reptile species, with taxonomy and literature.
- GBIF Backbone Taxonomy (Global Biodiversity Information Facility) Peer-reviewed researchInternational scientific taxonomy used here for classification.
- Wikipedia (species article) Community referenceFree encyclopedia; useful overviews with their own citations. Intro text is quoted under CC BY-SA 4.0.
- PubMed (U.S. National Library of Medicine) Peer-reviewed researchIndex of peer-reviewed veterinary, zoo and husbandry research.
- iNaturalist (captive observations) Community referenceCommunity observation platform run by the California Academy of Sciences and National Geographic; observations marked captive show animals living in homes, zoos and aquariums.