Common flat-tail gecko

About the species

Uroplatus fimbriatus is one of the largest geckos in the genus, and the species name means fringed. Along the body, legs and edge of the tail there are narrow flaps of skin, which lie flat against the bark when the animal rests on a trunk. They erase the shadow of the body, so that the gecko no longer looks like an animal. The colours are grey, brown and greenish and often marbled like moss and lichen, and the broad, flat tail looks like a withered leaf.

Adults reach 25-33 cm including the tail. There are no reliable weight figures for the species, so weight is not given in the fact box. The eyes are large and lidless, with a vertical pupil, and so sensitive to light that the gecko can see colours at night. If disturbed, it raises its head and tail, opens its mouth wide and screams. It is a bluff, but it works.

The species was described as early as 1797 by the German naturalist Johann Gottlob Schneider under the name Stellio fimbriatus and is the type species of the genus. In 2006 the large leaf-tailed geckos from northern Madagascar, including Montagne d'Ambre, were split off as a separate species, Uroplatus giganteus, so older reports of very large animals from the north probably concern that species.

This is an animal for someone who wants to watch and has patience, not for someone who wants a pet. A large share of the animals in the trade have been wild-caught and have arrived stressed, dehydrated and full of parasites, so choose a captive-bred animal if you can.

Care

The enclosure

The species uses height, so the enclosure must be tall. A single adult can manage in 45 × 45 × 90 cm (length × width × height), but a pair should have at least 60 × 60 × 100 cm, the same minimum that EAZA recommends for a pair of the somewhat smaller Henkel's leaf-tailed gecko. A male with two females needs about 60 × 60 × 120 cm or more. Juveniles do well in a smaller enclosure of about 30 × 30 × 45 cm.

Glass walls hold the droplets from misting, and the animals drink from them. The front and top should have mesh, so that the air is exchanged. Furnish with vertical and sloping branches, cork bark and thick bamboo tubes at different heights, so that the gecko can sit head-down as in the wild. Plants with large leaves, live or artificial, provide cover and hold the humidity.

A damp mixture of coconut fibre and unfertilised soil, covered with dead leaves, works as a substrate. For newly hatched juveniles, kitchen paper is the safest, because they cannot swallow any of it. Remove droppings often, and change the substrate completely at regular intervals, because moisture and droppings quickly breed bacteria.

Temperature

The species tolerates heat poorly and should be kept cooler than many people think. By day 22-25 °C is suitable, and at night the temperature should fall to 17-21 °C. The night-time drop is an important part of the daily rhythm. The sources agree that the temperature may only briefly exceed about 27 °C, and above 30 °C the risk of deaths rises quickly.

In an ordinary Danish living room, extra heat is usually unnecessary. The sources disagree about a warm spot: one recommends a small basking spot of 27-28 °C, while others advise against anything above 27 °C. For that reason no hot spot is given in the fact box. If you want a small warm spot, keep it at no more than 27 °C, and make sure the animal can always seek a cooler place.

Measure with two digital thermometers, one at the top and one at the bottom, and place the enclosure away from sunny windows. A thermometer with an alarm quickly reveals a heatwave, and on hot summer days a fan above the mesh lid can be enough to keep the temperature down.

Humidity and water

High humidity is the most important part of care, because the species dries out easily. Keep humidity at 65-70 % by day and 80-95 % at night, and let the substrate dry out a little during the day. Mist thoroughly with lukewarm water at dusk, so that there are droplets on leaves, branches and glass. A rain system with a fine mist running a couple of times a day is a great help.

The gecko drinks droplets from leaves and glass and seldom uses a water bowl, but provide a shallow bowl of fresh water all the same. Good ventilation is just as important as humidity, because stagnant, humid air causes mould, respiratory infections and skin problems. A hygrometer shows whether the routine is holding.

Lighting and UVB

The species is active at dusk and at night and belongs to Ferguson zone 1 together with other shade-dwelling species. There is little documented experience with UVB for this particular species, but a weak UVB light is now recommended for the whole genus. Use, for example, a T5 tube for forest species, so that the UV index is at most about 0.6-1.4 on the uppermost branches, and place it on one side, so that the rest of the enclosure is in shade. By comparison, EAZA allows up to UV index 3 right up under the lamp for Henkel's leaf-tailed gecko, but more than zone 1 is not necessary here.

Keep the light on for 10-12 hours a day, controlled by a timer, and ensure darkness at night. Avoid strong spotlights and coloured night light. Strong light and heat together are the quickest route to a stressed gecko.

Feeding

The species eats insects and takes almost only live prey. Offer a mix of crickets, locusts, dubia roaches and large mealworms, and waxworms as a treat. Prey must not be wider than the distance between the gecko's eyes. Feed juveniles every day or every other day and adults 2-3 times a week, as much as they eat in 10-15 minutes. Weight should be kept stable.

Dust the insects lightly with calcium, and give vitamin D3 and multivitamin a couple of times a month. Females in the breeding season need extra calcium. Feed the feeder insects well before they are served, and remove the insects that are not eaten.

Small, captive-bred snails are worth trying, especially for females. In Henkel's leaf-tailed gecko they are crucial for the females' calcium supply and egg-laying, and it is likely that the same applies here, although it has not been studied. A few keepers give large females a newborn mouse once in a blue moon, but it is not necessary and can make the animal fat.

Behaviour and handling

The gecko relies on camouflage rather than flight and is shy and sensitive to stress. Wild-caught animals jump and may bite when touched. Captive-bred animals are calmer, but they too are unsuited to frequent handling. Keep the species as an animal to watch, and pick it up only when necessary. Sit low, and let it walk from hand to hand rather than holding on.

Sexually mature males must be kept apart, because they gape at each other and fight. The species is thus less peaceful than Henkel's leaf-tailed gecko. A pair or a male with two females can work in a large enclosure with many hiding places. Look for wounds, especially in the breeding season, and separate the animals if there is unrest. If the gecko screams when you approach, you have come too close.

Breeding

Sexual maturity and sexing

Males are recognised by a distinct bulge at the base of the tail, where the hemipenes lie, and by small pores in front of the vent. Females are usually slightly larger and get a fuller body when they are ready to breed. There are no reliable figures for when the species reaches sexual maturity in captivity, so age is not given in the fact box. Wait until the female is fully grown and in good condition before she is put to breed.

A female in good condition has distinct white calcium pouches on the neck, where she stores calcium for the eggs. Sex is determined by chromosomes: a 2023 study of several Uroplatus species suggests that the whole genus has males with ZZ and females with ZW.

Mating

Mating takes place at night and can last several hours. The male waves his tail, climbs onto the female without biting her neck and brings his tail in under hers. The female can store sperm and lay several clutches after a single mating, so the male can be removed again after a few weeks.

Introduce the male to the female, and watch them for the first few nights. If you have several males, they must take turns being with the females and never be together. Give the female at least three months' rest from the male every year, preferably in the cooler period, so that she can rebuild calcium reserves and weight. Stable high humidity and regular misting are a prerequisite for getting the species to breed.

Egg-laying and clutches

The female usually lays one or two eggs, often three to four weeks after mating. How many clutches a female lays per year is not documented for the species, so it is not given in the fact box. In Henkel's leaf-tailed gecko a female can lay up to five clutches in a season, and this gives an idea of what to expect.

The eggs are round and hard-shelled. The female lays them on the ground under the leaves or lightly buried and rolls them in soil while the shell hardens. Give her a quiet laying site, for example a tray or pot with slightly damp soil and a layer of leaves. Look for eggs every day when she seems restless, and never turn them when you pick them up.

Incubation

Place the eggs half-buried in vermiculite (mixed 1:1 with water by weight) or damp sphagnum in a small box with a few ventilation holes, without turning or covering them. Humidity in the box should be above 70 %, but the eggs themselves should stay dry.

There are only a few documented figures for this particular species. A single breeder describes hatching after 100-120 days at about 24-26 °C. The figures in the fact box are borrowed from EAZA's guidelines for Henkel's leaf-tailed gecko: 18-26 °C, preferably with a night-time drop to 18-22 °C, and 100-230 days with an average of 165 days. Higher temperatures give a shorter time. Use them as a guide, not as the answer, and be patient before you give up on an egg. Whether temperature can affect the sex of the young has not been studied in the species.

Rearing the young

Newly hatched juveniles are about 5-6 cm long and live off the yolk remnant for the first few days. Move them to a small enclosure with kitchen paper, branches and a plant, and keep it damp. Juveniles must be kept apart from the adults.

Give small crickets and fruit flies, dusted with calcium, every day or every other day, and make sure the prey is not too large. There are no species-specific temperature figures for juveniles, but EAZA's recommendation for juvenile Henkel's leaf-tailed geckos, 23-25 °C by day and 19-21 °C at night, is a reasonable starting point. Weigh the juveniles regularly. They grow quickly in the first year, but there are no reliable figures for when they are fully grown.

Health and common mistakes

Wild-caught animals are often weakened, and this is the greatest risk with the species. Otherwise most problems are caused by wrong conditions in the enclosure. The typical mistakes are:

• Too high a temperature. A longer time above 27 °C stresses the animal, and above 30 °C it may die.
• Dehydration because of too low humidity. The gecko drinks droplets, so mist daily.
• Too little calcium and vitamin D3, especially in breeding females, which causes soft bones and eggs that become stuck.
• Parasites and infections in wild-caught animals. Have a faecal sample examined by a vet with reptile experience, preferably before the animal moves in with your other animals.
• Stagnant, humid air, which causes mould and respiratory infections.
• Stress from handling, strong light and disturbance, which can make the animal stop eating.

A healthy animal has clear eyes, a plump tail and a good grip. Seek a vet if the gecko loses weight, does not eat for a couple of weeks, breathes with difficulty or seems lethargic.