A brilliant emerald-green, diurnal arboreal gecko from Madagascar, prized for its bold daytime activity and red dorsal markings; a look-but-handle-rarely display species.
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The largest living day gecko: adults up to 28-30 cm (11-12 in) total length.
Lifespan
6–15 years
Social needs
solo
Native region
Northern Madagascar (introduced to Florida, Hawaii, and elsewhere)
Origin
Old World
Climate
🌴 Tropical
Family
Gekkonidae
Genus
Phelsuma
Part of the Geckos
Geckos range from desert ground-dwellers to humid cave and forest specialists; eyelid geckos like Goniurosaurus and leopard geckos have movable eyelids and are largely terrestrial.
From the minimum an animal needs to be kept humanely, up to the ideal setup. Bigger is almost always better — minimums are floors, not targets.
Photo coming soon
Minimum
Tall arboreal vivarium
18 × 18 × 24 in
Phelsuma grandis is a large diurnal day gecko. Single adult needs an 18×18×24 vertical with bamboo, live pothos, strong UVB (10–12%), and a basking spot of 32–35 °C. Humidity 60–80%.
Photo coming soon
Recommended
Planted vertical vivarium
24 × 24 × 36 in, planted
A 24×24×36 with dense tropical planting, bamboo perches, and strong UVB across the basking zone. Mist twice daily. Males are territorial — keep solo or 1.1.
Photo coming soon
Ideal
Large bioactive vivarium
36 × 24 × 48 in, bioactive
Bioactive Madagascan forest enclosure with broad-leaf plants, varied climbing structure, and natural-cycle lighting. Lets a pair display courtship and territorial behaviour naturally.
Life & growth stages
How this animal changes through its life — each stage often has its own care, diet and space needs.
Photo coming soon
Egg / Neonate
Most reptiles lay leathery- or hard-shelled eggs incubated by ambient warmth, though some snakes and lizards give live birth. Incubation temperature can influence sex and development in many species.
Photo coming soon
Hatchling
Hatchlings emerge as fully formed miniatures of the adult, often using an egg tooth to slit the shell. They are independent from birth but small and vulnerable, and may show brighter or different juvenile patterning.
Photo coming soon
Juvenile
Juveniles grow steadily, shedding their skin periodically as they enlarge. Coloration and proportions shift toward the adult form, and growth rate depends heavily on temperature, diet, and basking/UVB access.
Adult
Adults reach the species' full length and mass and become sexually mature. Many reptiles show sex differences in size, coloration, or features (such as larger heads, hemipenal bulges, or femoral pores), and continue to shed throughout life.
Color & pattern variants
Natural variants occur in the wild; selectively bred (man-made) variants were developed in captivity.
House one adult in a tall, planted arboreal terrarium of at least 18 x 18 x 24 in (45 x 45 x 60 cm), larger if possible, oriented vertically with bamboo, cork, vines, and live broadleaf plants (pothos, Sansevieria, bromeliads) that double as cover and egg-laying sites. As a strong climber with adhesive toe pads it uses every inch of vertical space. A bioactive or coco-fiber substrate helps hold humidity.
Because it is strictly diurnal, this species genuinely requires UVB: provide a quality UVB lamp (around 5-7%) on a 12-hour cycle, plus a basking spot of 90-95F (32-35C) and an ambient gradient of 78-85F (26-29C) dropping into the low 70sF at night. Maintain humidity around 60-80% with daily misting and good airflow. Provide a small live or artificial plant cluster for the gecko to wedge eggs against, as females glue their hard-shelled eggs to surfaces.
Substrate
A bioactive, moisture-retentive substrate (coco fiber, soil, and leaf litter over a drainage layer with a cleanup crew) sustains the high humidity these geckos require; coco coir or sphagnum-topped mixes are simple alternatives, and paper towel suits quarantine.
Equipment & setup
House in a tall, planted, well-ventilated terrarium (at least 18x18x24 in) with bamboo, cork, and broad-leaved plants. Provide a basking spot of 85-90°F (ambient 78-82°F) via an overhead bulb on a thermostat and, critically, strong UVB (T5 5-7%) since this diurnal species needs it; maintain 60-80% humidity with daily misting or an automatic mister.
Diet
An omnivore that needs both insects and a sugary nectar/fruit component. Offer a rotation of gut-loaded crickets, dubia roaches, and other appropriately sized insects 2-3 times weekly, dusted with calcium and (because of indoor UVB limits) periodic D3 and multivitamin.
In addition, provide a commercial powdered day-gecko/crested-gecko diet or fruit puree (mango, banana) mixed with water in a small ledge dish 2-3 times weekly; this mimics the nectar and pollen they lick in the wild. Provide water through misting droplets and a shallow dish.
Behavior & temperament
Active, alert, and visually striking during daylight, which makes it an excellent display animal, but it has delicate skin that tears easily and it dislikes restraint, so handling should be minimal and gentle. Stressed or grabbed individuals may drop the tail (which regenerates) or shed patches of skin.
Enrichment comes from a tall, densely planted enclosure with varied perches, basking sites, and UVB-lit gradients that let it thermoregulate and forage naturally. House adults singly: this is a highly territorial species, and two adults (especially males) will fight, often fatally; even male-female pairs need ample space and monitoring.
Health
The most common problems are metabolic bone disease from inadequate UVB or calcium (this species is especially prone because of its high UVB needs), and dehydration or shedding issues from low humidity. Reliable UVB, calcium supplementation, and consistent misting prevent most cases.
Females are prone to egg-binding (dystocia) and calcium depletion from frequent clutching, so breeding females need extra calcium and a laying site. Watch for skin tears, retained shed, weight loss, and parasites; quarantine new animals and use a reptile veterinarian for fecal screening and for any tremors, jaw softening, or lethargy.
Tips, DIY & hacks
These bold but fragile-skinned geckos should be viewed more than handled, as their delicate skin tears easily. Offer a complete powdered diet plus gut-loaded insects and occasional fruit/nectar, give them vertical bamboo and smooth leaves to perch and lay eggs on, and house only singly or as bonded pairs since they are highly territorial.
