| Pygmy mulga monitor | |
|---|---|
 | |
| Alice Springs Desert Park | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Order: | Squamata |
| Family: | Varanidae |
| Genus: | Varanus |
| Subgenus: | Odatria |
| Species: | V. gilleni |
| Binomial name | |
| Varanus gilleni | |
| Synonyms [4] | |
| |
The pygmy mulga monitor (Varanus gilleni), also known commonly as Gillen's monitor or just the mulga monitor, is a species of lizard in the family Varanidae. [5] The species is endemic to Australia.
The original description of the species V. gilleni was presented to the Royal Society of Victoria in 1895 by Arthur H. S. Lucas and Charles Frost. [2]
The specific name, gilleni, is in honor of Australian anthropologist Francis James Gillen. [6]
V. gilleni is native to the spinifex sandplains of northwestern and central Australia. [7] It can be found under the loose bark of desert she-oaks, and the hollows of eucalyptus, mulga, and myall trees. [8]
The pygmy mulga monitor is arboreal, with a prehensile tail. It grows to a total length (including tail) of around 40 cm (16 inches). The upper surface is brown, grading to grey at the sides. The nostrils are positioned on the sides of the muzzle, about halfway between the tip of the snout and the eye. [7] V. gilleni weighs, on average, 60–80 grams (2.1–2.8 oz). [9] Males and females can be distinguished by the presence of spines on the sides of the male's vent. [5]
It is sometimes mistaken for the stripe-tailed goanna, but the two species are allopatric and can be physically distinguished by the pygmy mulga monitor's slightly larger size. [8]
This species has very high endurance, owing to it having one of the highest factorial aerobic scopes of any vertebrate. A study where individuals were placed on treadmills running at a speed of 1 kilometre per hour (28 cm per second) found that they could maintain the speed for "many minutes" without tiring. [10]
It is particularly well adapted to arid conditions, losing water at half the rate of other Australian monitor species. [5]
Although an arboreal lizard, much of the prey of V. gilleni is found by foraging on the ground. Pygmy mulga monitors eat primarily spiders, orthopterans, beetles, and other lizards, especially geckos such as Gehyra variegata and Heteronotia binoei . [8] Geckos too large to be killed may be attacked anyway to consume their autotomized tails. [8] Bird eggs, small mammals, and even ant-sized prey are also taken. [5]
Ritualized fighting sometimes occurs between males of V. gilleni. Unlike larger monitors which grapple with each other while standing on their hindlegs, they grapple each other with all four limbs, belly to belly, and roll around on the ground trying to force the other onto its back. [5] Biting may also occur.
Breeding likely takes place between September and October. [8] A clutch of up to seven eggs may be laid in a burrow that is 30 cm (12 in) deep, which may then be sealed with sand. The eggs hatch after three months. [5]
The species V. gilleni is predated on by birds of prey, snakes, and larger monitors such as Gould's monitors. [8]
Monitor lizards are lizards in the genus Varanus, the only extant genus in the family Varanidae. They are native to Africa, Asia, and Oceania, and one species is also found in the Americas as an invasive species. About 80 species are recognized.
A goanna is any one of several species of lizard of the genus Varanus found in Australia and Southeast Asia.
The Bengal monitor, also called the common Indian monitor, is a monitor lizard distributed widely in the Indian Subcontinent, as well as parts of Southeast Asia and West Asia. This large lizard is mainly a terrestrial animal, and its length ranges from about 61 to 175 cm from the tip of the snout to the end of the tail. Young monitors may be more arboreal, but adults mainly hunt on the ground, preying mainly on arthropods, but also taking small terrestrial vertebrates, ground birds, eggs and fish. Although large Bengal monitors have few predators apart from humans who hunt them for meat, younger individuals are hunted by many predators.
The lace monitor, also known as the tree goanna, is a member of the monitor lizard family native to eastern Australia. A large lizard, it can reach 2 metres (6.6 ft) in total length and 14 kilograms (31 lb) in weight. The lace monitor is considered to be a least-concern species according to the International Union for Conservation of Nature.
The black tree monitor or Beccari's monitor is a species of lizard in the family Varanidae. The species is a relatively small member of the family, growing to about 90–120 cm (35–47 in) in total length. V. beccarii is endemic to the Aru Islands off New Guinea, living in an arboreal habitat. The skin color of adults is completely black, to which one common name refers.
The crocodile monitor, also known as the Papuan monitor or Salvadori's monitor, is a species of monitor lizard endemic to New Guinea. It is the largest monitor lizard in New Guinea and is one of the longest lizards, verified at up to 255 cm (100 in). Its tail is exceptionally long, with some specimens having been claimed to exceed the length of the Komodo dragon, however less massive.
The mangrove monitor, mangrove goanna, or Western Pacific monitor lizard is a member of the monitor lizard family with a large distribution from northern Australia and New Guinea to the Moluccas and Solomon Islands. It grows to lengths of 3.5 to 4 ft.
The short-tailed pygmy monitor is the second smallest living monitor lizard in the world with a maximum length of 25 cm.
Varanus timorensis, the Timor monitor or spotted tree monitor, is a species of small monitor lizards native to the island of Timor and some adjacent islands.
The emerald tree monitor or green tree monitor, is a small to medium-sized arboreal monitor lizard. It is known for its unusual coloration, which consists of shades from green to turquoise, topped with dark, transversedorsal banding. This coloration helps camouflage it in its arboreal habitat. Its color also makes the emerald tree monitor highly prized in both the pet trade and zoos alike.
The spiny-tailed monitor, also known as the Australian spiny-tailed monitor, the ridge-tailed monitor the Ackie dwarf monitor, and colloquially simply ackie monitor, is an Australian species of lizard belonging to the genus of monitor lizards (Varanus).
The stripe-tailed goanna, also known as the line-tailed pygmy monitor is a semi-arboreal species of monitor lizard native to Western Australia.
The Kimberley rock monitor is a medium-sized species of monitor lizard in the family Varanidae. The species is native to Northern Australia. Also known commonly as Glauert's monitor and the Kakadu sand goanna, it belongs to the subgenus Odatria.
The black-headed monitor or black-tailed monitor is a relatively small species of monitor lizards native to Australia. It is occasionally also called the mournful monitor, freckled monitor or the racehorse monitor, a name it shares with the Gould's monitor due to their exceptional speed. It is placed in the subgenus Odatria.
The Pilbara monitor, also known commonly as Bush's monitor, Bush's pygmy monitor, and the Pilbara mulga goanna, is a species of monitor lizard in the family Varanidae. The species is endemic to Australia.
The rusty desert monitor is a species of small monitor lizards native to Australia. It is also known as the pygmy desert monitor. The monitor lizard belongs to the subgenus Odatria along with the pygmy mulga monitor. This monitor lizard is oviparous as with other monitor lizards.
Storr's monitor is a species of monitor lizard in the family Varanidae. The species is endemic to Australia.
Odatria, commonly known as dwarf monitors, consists of small monitor lizards found in Australia and Indonesia. Species in this subgenus include the smallest monitor species in the world, the tiny 16 gram Dampier Peninsula monitor, but also includes some more medium sized species such as the 240 gram black-palmed rock monitor.
