Virtually unknown in captive collections until 1994 when specimens of T. gracilis and T. novaeguineae were imported from the Indonesian country of Irian Jaya on the western end of the island of New Guinea. Little information is available on their natural habitat, although they have been collected in moist habitat along waterways at fairly high elevations.
Approximately two and one-half inches long at birth, they average about eight to ten inches in length as adults. Juveniles are dark brownish black with a thin white or cream mid-dorsal stripe. Adult specimens are solid dark reddish brown with a startlingly bright orange ring around the eye. Some captive-bred specimens have varying amounts of gold flecking on the toes and face. It is not know whether this is genetic or dietary in nature.
‘Tribbies’, as they are affectionately known, will rarely attempt to bite, although they may do so if restrained. Handle gently, without pinching or squeezing. Remember that the tail may break off if handled roughly, and although it will regenerate, it will not appear original. Until accustomed to handling; the lizard should be handled inside the cage or while sitting on the floor. A frightened lizard may leap out of the keepers’ hand and take a fatal fall if held while standing. Juveniles may play dead if frightened, and this display is so convincing that we once discarded a live one into the trash before realizing our mistake!
Just about anything can be used, with a ten gallon aquarium being adequate for a pair. When selecting a cage, pay special attention to the humidity needs of these lizards. Screen covers provide excessive air flow and should be avoided. While they cannot climb smooth surfaces, these lizards have sharp little claws and climb branches with ease.
These lizards prefer a very high humidity level, and we suggest the use of cypress mulch to aid in increasing humidity. We have successfully maintained these lizards into the third generation by keeping them in 28qt Rubbermaid containers with a 2" deep layer of damp cypress mulch as substrate.
A variety of small insects and arthropods are eagerly accepted by ‘Tribbies’. Hatchlings will feed on two to three week crickets and wax-worms. As they grow, provide larger crickets, wax-worms, and mealworms. Adult specimens will take an occasional pinkie mouse. Dust food with a calcium powder about twice a week to provide additional calcium for growing bones. Adults may be supplemented once weekly, unless females are producing eggs. This uses huge amounts of calcium, and supplements should be made daily.
Provide clean water in a shallow dish. Humidity should be high, and these lizards seem to enjoy occasional misting. If kept too dry, these lizards often experience shedding problems, particularly the toes and spines along the back. Providing a small plastic container with lid (cut an access hole in the side) filled with damp sphagnum moss will allow the animal to shed properly. Stuck sheds on toes may harden and constrict the blood flow to the toes, causing loss of the toes. We place our animals into a soak bucket of tepid water 1" deep for about an hour once each week. Stuck shedding is easily removed at this time. It may be necessary to reduce ventilation of the cage to increase humidity within, if shedding problems are consistently encountered.
Provide a thermal gradient by placing a heat pad under one end of the cage. This should allow the lizards to choose from higher temperatures (about 82F) at the warm end, and cooler temperatures (about 72F) at the cooler end. Provide suitable hiding areas at both warm and cool areas, so the lizards can feel secure at any temperature. Temperatures below 65F should be avoided. No special lighting is required for these nocturnal animals.
Males are slightly larger than females, and can be distinguished by the presence of thin rows of pads on three of the rear toes, and a small square of enlarged belly scales at the location where you would expect a ‘belly-button’. Do not keep more than one male per cage as they may fight in the presence of sexually ripe females. We have also experienced problems keeping mature females together, and now maintain our animals in pairs. We have experienced no problems keeping pairs together for five years. While there appears to be no definite breeding season for these animals, we have noticed an increase in egg production in late fall. Eggs are laid singly, usually every five weeks, although there is much variation. Incubation can take from 42 to 83 days (avg. 60), the length of time is not related to temperature. We have successfully hatched T. gracilis at a wide range of temperatures, although temperatures over 81F have proven fatal. About 76F, seems to be optimal, and daily fluctuation has not proven to be detrimental. We suspect that there is a poorly defined diapause period, possibly triggered by moisture content, which is responsible for the wide variance in incubation times. The sex of the hatchlings is not temperature dependent. While life-span is not known with certainty, all of our original animals are still thriving and reproducing after five years. A single specimen was maintained at Dallas Zoo for over ten years. Sexual maturity is attained in the third year. Much more study is needed to gain a better understanding of these fascinating lizards.
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