Australian spiny-tailed monitor, Ridge-tailed monitor, Ackie's dwarf monitor, Ackie monitor
The Spiny-tailed monitor (Varanus acanthurus) is a burrowing species of lizard found in Australia. It is also known as the Australian spiny-tailed monitor, the Ridge-tailed monitor, the Ackie's dwarf monitor, and colloquially simply Ackie monitor.
Di
DiurnalDiurnal animals are active during the daytime, with a period of sleeping or other inactivity at night. The timing of activity by an animal depends ...
Ca
CarnivoreA carnivore meaning 'meat eater' is an organism that derives its energy and nutrient requirements from a diet consisting mainly or exclusively of a...
Te
TerrestrialTerrestrial animals are animals that live predominantly or entirely on land (e.g., cats, ants, snails), as compared with aquatic animals, which liv...
Ov
OviparousOviparous animals are female animals that lay their eggs, with little or no other embryonic development within the mother. This is the reproductive...
Pr
PrecocialPrecocial species are those in which the young are relatively mature and mobile from the moment of birth or hatching. Precocial species are normall...
Bu
BurrowingA burrow is a hole or tunnel excavated into the ground by an animal to create a space suitable for habitation, temporary refuge, or as a byproduct ...
Pr
PredatorPredators are animals that kill and eat other organisms, their prey. Predators may actively search for or pursue prey or wait for it, often conceal...
So
SolitaryNo
Not a migrantAnimals that do not make seasonal movements and stay in their native home ranges all year round are called not migrants or residents.
S
starts withThe Spiny-tailed monitor, a medium-sized monitor lizard, can attain a total length of up to 70 cm (27 in), although there are unconfirmed reports of wild individuals growing up to 34 inches. The tail is about 1.3-2.3 times as long as the head and body combined. The upper side is a rich, dark brown and painted with bright-yellowish to cream spots, which often enclose a few dark scales. Its tail is round in section and features very spinose scales. There are 70-115 scales around the middle of the body. The Spiny-tailed monitor is distinguished from the similar-looking species V. baritji and V. primordius by the presence of pale longitudinal stripes on the neck.
These lizards are found in northern Western Australia, in the Northern Territory, and in the western and north-western parts of Queensland. They inhabit savanna woodlands with arid rocky ranges and outcrops.
Spiny-tailed monitors are diurnal, typically solitary ground-dwellers. They are most often found in their shelter, mainly under rock slabs, wedged among boulders or in rock crevices, and in underground burrows. Only rarely do they hide in spinifex. Sheltering underground gives them access to humid microclimates which helps keep them hydrated enough to survive the otherwise arid nature of their habitat.
Spiny-tailed monitors are carnivores. They prey mainly on grasshoppers, beetles, cockroaches, spiders, isopods, caterpillars, cicadas, snails, stick insects, centipedes, crickets, and ticks. Small lizards such as skinks, geckos, or dragon lizards are also eaten, making up about a third of their diet. Approximately 70% of their water requirement comes from food.
Spiny-tailed monitors breed in spring. Females lay 5 to 15 eggs in the nest chamber dug in the soil. Females may even share massive burrows, nesting communally. The eggs are incubated for about 120 days and fully-developed hatchlings dig themselves out of the nest. They typically hide under cover from predators and are able to get their food without parental help.
There are no major threats to this species at present.
According to IUCN Red List, the Spiny-tailed monitor is locally common throughout its range but no overall population estimate is available. Currently, this species is classified as Least Concern (LC) on the IUCN Red List.
