Central Earless Dragons 

With the kind permission of author Joe Auliffe

The Central Earless Dragon is one of eight small lizards belonging to the genus Tympanocryptis. This small group of dragons collectively occupies every state in Australia with the exception of Tasmania. The common name ‘Earless Dragon’ applied to this group of lizards is not entirely accurate. They do have ears, the scientific name  Tympanocryptus means hidden ear. The ear in this genus is concealed by a layer of scaled skin, making the dragons appear ‘earless’.

The Central Earless Dragon or Tympanocryptus centralis is a small species with a snout vent length of 55mm. It is distinguished from other members of the Tympanocryptus genera by the presence of distinctly keeled scales on the top of the head and the neck being much narrower than the base of the head. Perhaps the easiest way to identify this species is by geographic locality. T. centralis natural distribution is from central Australia, chiefly from the Western MacDonnell Ranges to far west Northern Territory near the Western Australian Boarder. Other species T. cephalus and T. lineata are only known to overlap with T. centralis in the northeastern part of its range.

Within its recognised range, the Central Earless Dragon is found on stony hills and plains quite often with a sparse vegetation cover. In the Western MacDonnell Ranges, this species has been observed in areas with embedded and loose rock formations. Males are often seen at the top of the tallest rock overlooking an open flat area. This not only provides an ideal place to bask but also a vantage point of his territory where he can observe females, rival males and potential predators. Females will also take up position on the tops of rocks, especially when gravid.

Looking for dragons on the rocks is the easiest way to locate them in their natural habitat. During the breeding season, females will spend most of their time in areas suitable for laying their eggs. At this time, they can be difficult to locate as their body pattern and colour help to camouflage them. So good is their ability to blend in with their surroundings, that the keen observer may only see them if and when they move just prior to stepping on them. Flat areas with a sparse herbaceous plant growth and fine sandy soils provide ideal nesting sites. Ideal locations in Western MacDonnell Ranges have been observed to contain hundreds of diggings from gravid females.

Captive Management

Earless dragon requirements are like those of many other Australian Agamids in that a combination of environmental factors such as heat and light and their variables are important components of successful captive management. Central Earless Dragons come from the centre of Australia, where daytime maximums of 40ºC+ are common with winter minimums of less than 0ºC. Healthy individuals in the wild may only have a life span of one to two years. Captive earless dragons also have short lifespan when compared to many other commonly kept dragons. Average life expectancy is about two years with some individuals reaching six to seven years of age.

Temperature and daylight cycling.

As with the keeping of many Australian Agamids, Central Earless Dragons respond well to the stimulus of a bright, heat emitting light source. Bright light stimulates activity in the dragons, stimulating feeding, breeding and other natural behaviours. It is important that the light source itself be suitable for basking dragons that require and benefit from an ultra violet light spectrum. In particular, UVA and UVB lights provide the best results.

Several light globe types are suitable for use with Central Earless Dragons. The use of each is influenced by the enclosure, its design, construction materials and level of temperature control sophistication, and all need to complement one another. For example, the author prefers the use of mercury vapour lights. These lights produce a lot of heat and are generally considered too hot for use in small enclosures. Some successful light/heat to enclosure design examples are below.

2½-foot timber enclosure with no thermostat control.

Daytime Light Source: Dichroic/Halogen 50w (basking)

Compact florescent (UV10)

Nighttime heat sauce: None

Summer Day to Night ratio up to 14:10

Winter Day to Night ratio 9:15

The light emitters provide a UV light source and heat source in one. The nighttime temperatures are allowed to fluctuate. This provides a naturalistic annual temperature cycle. Day and night cycles are maintained at natural levels throughout the year.

2½-foot timber enclosure with thermostat control.

Daytime Light Source: Compact florescent UV10

Nighttime heat sauce: 100w Ceramic controlled by Digital day/night cycle thermostat

Summer Day to Night ratio up to 14:10

Winter Day to Night ratio 9:15

The light emitter provides a UV light source. Day and nighttime temperatures are controlled by the thermostat / ceramic globe combination. Typical temperature settings on the thermostat are 30ºC to 35ºC during day light hours, and allowed to fall to 10ºC to 15ºC at night. Summer nighttime minimums may be naturally higher, effectively greater than the thermostat night setting. This will result in the heat emitter not coming on and hence allow natural temperature fluctuation throughout the year.

120lt (or larger) plastic storage container (without lid)

Daytime Light Source: 125w to 160w Mercury Vapour or

100w+ Neodium globe

Nighttime heat sauce: Heat cord under tub. Sparsely looped to provide mild heat. Only used in winter.

Summer Day to Night ratio up to 14:10

Winter Day to Night ratio 9:15

This is the preferred method use by the author. One light is placed at one end of the enclosure, suspended approximately 6 to 10 inches above the basking site. The heat cord can be run dimmed or spread out to provide a subtle substrate heat. This is run constantly during the cooler winter months. It is switched off for the remainder of the year.

Substrate and furnishings.

This is only limited to the keeper’s imagination and the size of the enclosure the dragons will be kept in. Enclosures can be decorated with all manner of materials in order to create a natural setting. Alice Springs Desert Park has successfully kept Central Earless Dragons for several years using this method. Alternatively, enclosures with minimal furnishings are also a highly successful way of keeping these little dragons.

There are however, some critical aspects of substrate selection and furnishing that dramatically affect natural behaviours. Dragons like to feel secure at night and Earless Dragons are no exception to this. Providing them with night hiding options such as amongst loose sand and pebbles, leaf litter or beneath timber and rocks are some proven methods. The dragons’ basking spot beneath the light is often a preferred resting place at night. The author prefers the use of rocks or bricks at the basking area which when the light switches off continues to radiate stored heat. 

Perhaps the most important component in the captive management of the Central Earless Dragons is the selection of the substrate. For successful breeding of this species, it is important to provide the female with a suitable medium in which to deposit her eggs. Females can be very particular and fussy when selecting a suitable site in which to lay their eggs. If she is not happy with the selection, she will not lay her eggs and may die from being eggbound.

The author has used a variety of substrates, but all need to fit a common set of needs. The substrate must not be overly compacted. Some substrates compact more than others, such as clays and silt based mediums, and generally these are avoided for these reasons. Sand based substrates that allow the dragon to dig into the medium without it collapsing when moist are ideal. The author has used red reptile sand, sandstone sand and loams successfully.

The substrate depth is another critical factor to get right. A minimum depth of 75mm to 100mm should cover the entire enclosure floor. Some areas should be mounded with additional substrate to provide deeper options for the female to lay. The author has observed that some females prefer to dig into the base of the mounded substrate. Some may dig anywhere, which is why a minimum substrate depth needs to be observed. However, most of the author’s females will lay in a depth of 100mm close to or under the basking furnishing. Usually females will dig multiple test burrows and select one in which to deposit her eggs. Once she has laid her eggs she will backfill the burrow with sand, disguising it so well that it is impossible to determine if a burrow was ever there. 

Diet.

Earless dragons are a ferocious feeder and will attack and attempt to eat anything that is large enough to be swallowed. However, it is best to feed the earless dragons small prey items. A good general rule practised by many dragon keepers is to feed insects that do not exceed the length between the dragons eyes. Doing so avoids many digestion issues that can arise from feeding larger prey items.

Adult earless dragons are usually fed small crickets or small cockroaches. Flies are among their favourite prey and they enjoy other invertebrates offered occasionally. Adult dragons have their food dusted with calcium and vitamin supplements three times per week.

Hatchling earless dragons measure only 22mm (svl) and are best fed on pinhead crickets or cockroaches up to 1 week old. The hatchlings will usually not need to feed for one or two days post hatching while their yolk is still being absorbed. Healthy hatchlings should be feeding within five days of hatching. If keeping the hatchlings together it is best to provide them with numerous pinheads every feed as they can become quite excited and are prone to bite their siblings’ tails. As calcium is an important component in the bone development of young dragons, every feed is dusted with calcium and vitamin supplements. This also allows the young dragons to pick off their prey without the insects escaping first.

One could be forgiven for thinking that dragons that come from the centre of Australia would not need to be provided with additional water. Certainly, adult earless dragons are capable of surviving and prospering without water for consecutive months, obtaining moisture from their prey. Hatchling and juvenile earless dragons should be lightly misted several times per week. This aids the digestive process in the young dragons and may help with the absorption of essential elements and vitamins.

Some Central Earless Dragon Facts

• SVL 55mm
• Colour generally brown through to brick red
• Average clutch size 7
• Maximum recorded clutch size 15
• Minimum clutch size 4