Frilled Lizard

Appearance

The frill-necked lizard is a relatively large member of the agamid family, growing up to 85 cm. It is capable of bipedal locomotion and has been described as regularly moving in this manner with a purposeful stride at times by naturalists.

Colouration tends to be brown or grey with spots and blotches of darker colours mixed in a mottled fashion to give the appearance of tree bark. There is not one standard colour: rather, colouration varies according to the lizard's environment. For example, a lizard found in a dryer, clay filled environment will most likely have a collage of oranges, reds, and browns; whereas a lizard found in a damper, more tropical region will tend to show darker browns and greys, and some greens. This suggests they are adapted to their habitats; their colours are a form of camouflage.

The most distinct feature of these lizards is the large ruff of skin which usually lies folded back against its head and neck. The neck frill is supported by long spines of cartilage which are connected to the jaw bones. When the lizard is frightened, it produces a startling deimatic display: it gapes its mouth, exposing a bright pink or yellow lining; it spreads out its frill, displaying bright orange and red scales; raises its body; and sometimes holds its tail above its body. This reaction is used for territorial displays, to discourage predators, and during courtship. The red and orange parts of its frill contain carotenoid pigments.

The bones of the frill are modified elongate hyoid types that form rods which expand the frill. Secondarily the frill can serve as a form of camouflage when relaxed; there is no standard colouration to the body, but it is usually darker than the frill.

Naming

Its common names come from the large frill around its neck, which usually stays folded against the lizard's body. "C. kingii" is largely arboreal, spending the majority of its time in the trees. Its diet consists mainly of insects and small vertebrates. Frill-necked lizards, or 'frillies' as some call them, will occasionally eat plants as well, although this behaviour is uncommon. It's a relatively large lizard, averaging 85 cm in total length and is kept as an exotic pet.

Distribution

The frilled-neck lizard is found mainly in the northern regions of Australia and southern New Guinea. The lizard on rare occasions is found in the lower desert regions of Australia but primarily inhabits humid climates such as those in the tropical savannah woodlands.

Habitat

It tends to be an arboreal lizard, meaning it spends a majority of its time in the trees. The lizard ventures to the floor only in search of food, or to engage in territorial conflicts. The arboreal habitat may be a product of the lizard's diet, which consists mainly of small arthropods and vertebrates. However, the trees are most importantly used for camouflage.

Reproduction

The frilled-neck lizard is sexually dimorphic; meaning that there are physical differences between male and females. This dimorphism is apparent in the length of the lizard; the male is generally larger than the female. There is little to no dimorphism in the colour of the lizard.

Frilled-necked lizards breed in the early wet season from September to October. Adult males fight for mates, displaying their frills and biting each other. One to two clutches of 6–25 eggs are laid from early to mid-wet season from November to February. The eggs are laid in a nest 5–20 cm below ground, and usually in sunny areas. Incubation takes two to three months. Gender is partly temperature determined, with extreme temperatures producing exclusively females, and intermediate temperatures producing equal numbers of males and females. Their eggs are soft-shelled.

Food

Like many lizards, frill-necked lizards are carnivores, feeding on cicadas, beetles, termites, and mice. They especially favour butterflies, moths and their larvae. Though insects are their primary source of food, they also consume spiders and occasionally other lizards. Like most members of the agamids, frill-necked lizards employ an ambush method of hunting, lying in wait for their prey. When the lizards eat, they eat in abundance; these binge periods usually occur during the wet season, when they ingest hundreds to thousands of alate ants or termites.

Predators

The species' main predators are eagles, owls, snakes, dingoes, quolls, and larger lizards such as goannas.