Giant leaf-tailed gecko (Uroplatus giganteus)
Keeping and breeding at BION Terrarium Center
DESCRIPTION, DISTRIBUTION AND BIOLOGY
Giant leaf-tailed gecko (Uroplatus giganteus Glaw, Kosuch, Henkel, Sound & Böhme, 2006) is a member of a so-called “U. fimbriatus group” of leaf-tailed geckos, that includes also Uroplatus fimbriatus (Linnaeus, 1758), Uroplatus henkeli Böhme & Ibish, 1990, Uroplatus sameiti Bohme & Ibish, 1990 and Uroplatus sikorae Boettger, 1913 (http://uroplatus.info/archives/70).
U. giganteus is the biggest species of the genus. Its SVL is 210–230 mm, TL is up to 110–120 (total length 310–325 mm). Total length of young geckos is 90–110 mm. U. giganteus at first glance resembles typical U. fimbriatus, but the color of iris is plain cream to white at daytime and develops a fine red stripe pattern after nightfall (http://uroplatus.info/archives/70) while U. fimbriatus demonstrates yellow color of the iris. Also morphology of hemipenises is a feature that helped scientists to find out that U. giganteus and U. fimbriatus are two different species (Glaw et al., 2006; Gehring et al., 2018). General build is rather flattened, with long skull and 28–40 supralabial scales. The dorsal basic color is white to beige; large brown to black bands and patches are scattered from the head to the tip of the tail. A broad dermal flap runs along the body with enlarged serrated extensions distributed at regular intervals. Adult males have well-seen hemipenal bulges (Svatek, van Duin, 2001; Glaw, Vences, 2007).
It is sometimes considered that giant leaf-tailed geckos can be sexed immediately after hatching. Male will have brownish hues with a clear diamond pattern on the back, turning into noticeable dermal spines in its angles. In contrast, female will have greenish shades and less noticeable spines. However, it should be noted that this approach is still discussable. The most reliable age of sexing is about 1 year when males start showing hemipenal bulges. The elder your animal is the bigger is the chance of correct sexing.
This species is endemic to Madagascar as well as other species from Uroplatus genus. They inhabit tropical rainforests of the eastern, northeastern, central and southeastern parts of Madagascar and the surrounding islands. They can be usually found on the lower parts of the trees to a height of 2 m, mainly on branches, trunks and vines (Bauer, 2013; Bohme, 2014). This species is endangered due to mass deforestation and decreasing of suitable habitats as a result of producing of tree coal by local people. Therefore development of breeding methods and creation of ex situ populations is extremely important (Dubyna et al., 2019).
U. giganteus tend to be quite aggressive. They usually try to bite a keeper while handling or sometimes during routine servicing of the enclosure. Protective behavior includes eyes’ bulging, opening of the mouth, and tongue showing. Also, they rise on their paws, raising and wagging the tail. The last warning is sharp aggressive attacks to the side of the stimulus. It is recommended to avoid such bites, as geckos can damage their jaws and consequently suffer from stomatitis later.
KEEPING AT BION TERRARIUM CENTER
Keeping. We keep these big lizards separately or in pairs (1.1) in 90*65*120 cm vertical terrariums. During the first 1.5–2 months of life we keep babies in 30*30*30 сm terrariums or plastic containers, that have good ventilation, with further moving to bigger boxes. The decoration of the terrarium consists of large vertical and horizontal branches for adult individuals and medium vertical and horizontal branches for juveniles, as well as lianas, living or artificial plants. We use big pieces of oak bark covering the bottom of the enclosure as a substrate for adults.
We keep juveniles for the first 6 months with a paper towel instead of bark substrate. Decoration includes thinner branches and smaller pieces of bark. Water dish is obligatory.
Lighting. We use Zoo Med 5 UVB or full spectrum lamps for lighting: at mating season for 12-14 hours a day; during other part of the year and prior to wintering it is 9-10 hours a day.
Temperature. We keep U. giganteus with daytime temperature of +24 – +26 °C, and nighttime temperature – +19 – +21 °C. We do not provide a basking spot.
Humidity. For both juveniles and adults we maintain air humidity of 75–90% with double spraying during the day.
Diet. For adult animals the diet consists of big locusts, Turkestan and marble cockroaches and crickets of adequate size. We offer 1–2 insects per animal 1–2 times per week and reduce the feeding sessions’ frequency to 1 time per 2 weeks in case any signs of obesity are seen. Sometimes if an animal is still hungry we can offer one or two additional feeding items. For females during ovogenesis we offer soft-shelled snails. Diet of juveniles is the same as for adults. Frequency of feeding: 2-3 insects per 1 young gecko 3 times a week. All insects should be gut loaded and dusted with vitamin-mineral supplementation every other feeding. Sepia or cuttlefish “bone” powder works well as a source of calcium.
BREEDING AND RAISING AT BION TERRARIUM CENTER
Winter dormancy is necessary for successful breeding. Animals are placed inside individual terrariums (females can be kept in groups (2-3 individuals), males - separately) with paper as a substrate. After placing the animals in a special laboratory, the temperature, spraying intensity (from 2 to 1 session per day) and daylight hours (by 1.5-2 hours per week) decrease within 2 weeks. Temperatures during wintering are as follows: +20 - +22 °C at daytime and +19 - +20 °С at nighttime. It is necessary to ensure that there are no signs of dehydration (twisted tail, clavicles visible, protruding hip bones). We provide 4 lighting hours a day. Wintering lasts for 2 – 2,5 months. We offer 1-2 low-fat insects per head, 1-2 times a week. Winter withdrawal algorithm is reverse to input and lasts for 2 weeks. After that we form pairs. During mating games, the male slowly approaches the female, regularly sticking out his tongue in a licking motion and shaking his tale. Copulation lasts about 20 minutes.
U. giganteus gain sexual maturity at the age of 2,5 – 3 year. Breeding season lasts from April to September. Females lay from 3 to 4 clutches per season (1–2 eggs in each). Females lay eggs in the substrate and cover them with bark or turf. Percentage of hatching is about 80%. Gestation period is about 30-50 days depending on the female. The eggs are transferred to the incubator without changing polarity. A small recess is made in vermiculite and each egg is placed in such a recess individually at no more than 2/3 eggs’ height depth. The eggs are incubated on vermiculite or “Seramis” substrate at +22 at night and +25 at day. Humidity is 75-85%. Incubation period is 120-140 days.
We keep juveniles separately. All keeping requirements are identical to those for adults. Hatchlings normally shed within a couple of days after hatching. If a baby cannot shed on its own, you can help it by tearing the linear peel on its face. But as a rule, most of these animals are weak and do not survive to reproductive age. Babies usually eat the shed skin. We believe that it is essential for appropriate functioning of digestive system.
1..Frank Glaw, Miguel Vences. 2007: Field Guide to the Amphibians and Reptiles of Madagascar. Vences & Glaw Verlag GbR 3rd Edition. 496 p. Germany.
2..Sacha Svatek and Susanna van Duin. 2001. Leaf-tailed geckos – the Genus Uroplatus. Brahmer-Verlag, 161 p. Germany.
3..Dubyna Anastasiia, Tkachev Dmitri, Neizhko Ivan, Nekrasova Oksana, Marushchak Oleksiі // Development of breeding techniques in herpetoculture as an approach to leaf-tailed geckos' (Gekkonidae, Uroplatus) conservation // Abstract book of 62nd International Conference for students of physics and natural sciences “Open Readings 2019” on March 19-22? Vilnius, Lithuania. – Vilnius. – 2019 – P. 467.
4..Frank Glaw, Joachim Kosuch, Friedrich-Wilhelm Henkel, Peter Sound & Wolfgang Böhme. 2006. Genetic and morphological variation of the leaf-tailed gecko Uroplatus fimbriatus from Madagascar, with description of a new giant species // Salamandra 42(2/3). – P. 129-144.
5..Philip-Sebastian Gehring, Souzanna Siarabi, Mark D. Scherz, Fanomezana M. Ratsoavina, Andolalao Rakotoarison, Frank Glaw, Miguel Vences. 2018. Genetic differentiation and species status of the large-bodied leaf-tailed geckos Uroplatus fimbriatus and U. giganteus // Salamandra 54(2). – P. 132-146.
6..Bauer A. M. 2013. Geckos - The Animal Answer Guide. Johns Hopkins University Press, 159 pp.
7..Böhme, Wolfgang 2014. Herpetology in Bonn. Mertensiella 21. vi + 256 pp.