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The Thorny Devil (Moloch horridus) is a small species of lizard native to the arid regions of Australia. Reaching lengths of 20 cm, this reptile has numerous adaptations which allow it to survive in its harsh environment. It is also one of the most recognizable lizards due to its unique spines and coloration. This article will discuss the biology, ecology, and conservation of the Thorny Devil.

Taxonomically, Moloch horridus belongs to the family Agamidae, within the order Squamata. The genus consists of two recognized subspecies: M. h. horridus and M. h. nudicollis with distinction based on geographic ranges; both found throughout mainland Australia but differing between Northern Territory/Queensland border and Western Australia respectively.

This species exhibits several distinct morphological characteristics such as an enlarged head crest along with low-lying rows of spiny scales that provide protection from predators when threatened or disturbed. Additionally, there are multiple thorny protuberances located around the body giving rise to its common name – ‘Thorny Devil’ – for which it is well known among many herpetologists and reptile enthusiasts alike.

Thorny devil

Species Overview

The thorny devil is an Australian lizard species of reptile in the family Agamidae. It is native to arid regions of Australia and can be found living on sandy soils amongst spinifex grasses, mulga shrubs and thickets of chenopods. This species has a unique appearance with its spiny body, hence the common name ‘thorny devil’. Its scientific name Moloch horridus derives from Latin meaning “horrible mole”.

This species typically grows up to 20 cm in length, although some have been known to reach 25cm as adults. The male’s base colour ranges from red-brown through grey-brown or olive green; while females are usually darker than males and may have tinges of blue or black along their back ridges.

They also possess two rows of dorsal scales running down their backs which consist of 28–44 large spines that run from neck to tail, giving them their distinctive look. Thorny devils have long claws used for digging burrows into sand where they sleep during extreme heat conditions or when drought occurs.

Thorny devils feed mainly on ants but can consume other small insects such as grubs, termites and beetles too. These lizards move slowly by foot over open surfaces using short steps, but can quickly turn around when threatened due to their ability to twist their bodies 180 degrees without turning their heads. They also use an interesting defense mechanism called ‘ant mimicry’, whereby it will lift its front legs off the ground whilst moving so it appears ant-like in order to deter predators away from itself.

Habitat And Distribution

The habitat of the thorny devil is concentrated in certain parts of Australia. It ranges from desert regions to arid habitats such as sandy areas and scrublands. As a result, it has become highly adapted to these conditions which are characterized by low rainfall and high temperatures.

This species can be found across much of mainland Australia; however its range does not extend into Tasmania or any other island off the Australian coast. The majority of populations exist within 500km radius of Alice Springs in Central Australia. There have been sightings further east on the South Coast but this is thought to be an isolated occurrence rather than part of a greater population pattern.

Given that they inhabit dry environments with little vegetation, thorny devils rely heavily on their ability to absorb water through their skin when available.

This means that even during times when there is no rain for prolonged periods, they can still survive provided that humidity levels remain above 10%. In order to meet these requirements, they will often bury themselves under sand or seek shelter beneath logs and rocks during the hottest parts of the day and come out at night when temperatures are cooler.

Some key points about where Thorny Devils live:

  • Found throughout most parts of mainland Australia
  • Not found in Tasmania or islands off Australian coast
  • Concentrations around Alice Springs in Central Australia
  • Prefer deserts, arid regions, sandy areas & scrublands
  • Need humidity levels over 10% for survival

Physical Characteristics

The thorny devil is easily identifiable due to its unique physical characteristics. Its body color ranges from tan, yellow-brown, and olive green. It has a triangular shaped head with small horns on the tip of its snout and two spines that protrude from the eyes.

Its length is determined by the number of spines between 11–18 cm long. Additionally, it has a short tail and forelegs that are about 4 cm in length when extended forward. The hind legs are much longer at around 8 cm.

This species does have remarkable defense mechanisms such as a sharp raised crest along its spine and neck region for protection against predators. They also possess skin flaps behind their front limbs which can be used to direct water droplets towards their mouths while drinking.

Furthermore, they are equipped with several other features like large scales over the lower parts of their bodies which provide an extra layer of armor or protection from any injuries they may encounter during their daily activities or interactions with other animals.

The thorny devil possesses many distinct physical traits which help to identify it within its natural environment. These include not only body coloration but also head shape, spinal length, tail length, and leg lengths. All these factors combine together to form this unique species that inhabits various habitats throughout Australia’s arid regions.

Diet And Feeding Habits

The diet of the Thorny Devil consists mainly of ants, though it will also consume other small insects such as termites, crickets and beetles. Research shows that approximately 95% of its diet is composed of ants. The remaining 5% include a variety of small invertebrates including spiders, beetles, moths and lizards.

When foraging for food, the lizard moves in an irregular pattern with alternating pauses at nearly every step. With each pause it sticks out its tongue to detect prey on the ground or nearby vegetation. Once prey has been located, the thorny devil uses its long sticky tongue to capture the item before swallowing it whole.

InsectsPercent (%)

This table displays the main components of a Thorny Devil’s diet and their percentage contribution to overall consumption. It can be seen that ant-eating forms the primary component 95% while termite-eating accounts for 2%, cricket-eating 1%, beetle-eating 1%, and finally lizard-eating represent just 1%.

Together these items form a balanced diet which helps keep this reptile healthy in its desert environment. In certain areas where food resources are limited they may resort to eating plants and flowers as well as carrion when available.

Reproduction And Lifespan

The reproduction cycle of the thorny devil is a complex process. The breeding habits and mating season can vary, depending on the climate and availability of food sources. Generally, they breed during late winter to early spring when temperatures are milder, allowing for more active movement in search of mates. During this period, males will compete with one another for access to females.

The birth process begins with fertilization of eggs by sperm within the female’s body prior to laying them. Following completion of incubation, she will lay her clutch of up to 20 eggs in a shallow nest or bury them in soil substrate where they remain until hatching. Once hatched, young lizardlings become completely independent from their mothers who provide no further care once the eggs have been laid.

Thorny devils typically live between 8-15 years in captivity but their lifespan expectancy in the wild is unknown due to difficulty researching these animals in their natural environment. This species has adapted well to its arid environment, enabling it to survive despite extreme conditions that other species may find inhospitable.

In some cases, individuals have been observed living past 15 years old when given proper care and protection from predators and environmental hazards such as fire or drought which could reduce their numbers significantly if not managed properly.

In summary, reproducing successfully is an important part of maintaining healthy populations of thorny devils throughout their range. Understanding their reproductive behavior and lifespans helps us better manage their habitats so that future generations can continue to thrive under optimal conditions.

Thorny devil

Conservation Status

The conservation status of the thorny devil is of great concern. This species is listed as Endangered on the IUCN Red List, meaning it is at risk of extinction in certain parts of its range. The main threats to this species are habitat loss and fragmentation due to agricultural expansion and urbanization.

In addition, they may be affected by climate change and increased temperatures. As a result, their population has declined significantly over recent years.

Various conservation efforts have been implemented in an attempt to protect this species from further decline. These include the establishment of protected areas such as national parks, wildlife reserves and bushland sanctuaries; increasing public awareness about these animals; and advocating for better environmental protection laws.

Additionally, research into their diet, behaviour, genetics and reproductive biology has helped identify key aspects that should be taken into account when managing their populations in the wild.

In order for effective management plans to be established for long-term conservation success, there needs to be more collaboration between authorities responsible for wildlife protection and those working towards habitat restoration or preservation initiatives. With concerted effort from all stakeholders involved, it is possible to ensure that the thorny devil will remain part of Australia’s unique biodiversity far into the future.

Interesting Facts

The Thorny Devil is a unique species which inhabits the deserts of Australia. It has an array of interesting traits that have assisted it in its survival and adaptation. This section will discuss these fascinating characteristics.

The habitat of the Thorny Devil is extremely dry, hot and arid regions with sparse vegetation. Its ability to survive in such harsh conditions relies on two distinct adaptations; one being its behavior and the other being its camouflage capabilities.

To conserve water, they hunt for food during the cool nights and remain inactive during warm days while burrowing beneath rocks or hiding under shrubbery. They are also able to absorb moisture from early morning dew after rainstorms due to their bumpy skin texture, enabling them to stay hydrated without having to drink much water.

Additionally, they possess several horns as well as brown splotches which help them blend into their surroundings like sandstone rock formations or scrubs in addition to providing protection from predators by appearing intimidating despite their small size.

Although not venomous themselves, Thorns Devils store poisonous secretions produced by ants inside grooves located on their back which act as deterrents against any potential attackers when released through glands found on either side of their head.

While this may seem unusual, it helps keep them safe given the dangerous environment they inhabit due to limited resources and competition for shelter with larger animals such as goannas and kangaroos amongst others.

In summary, the Thorny Devil possesses many remarkable features that make it uniquely adapted to life in its desert home including efficient hunting habits, effective camouflage abilities and toxic ant secretion storage. The combination of all three provides an impressive defense system unparalleled among most reptiles living in similar habitats around the world today.


The thorny devil, a lizard native to Australia, is an interesting creature due to its unique physical characteristics and behavior. With the ability to blend into their environment, they have adapted well in arid climates and are able to survive with very little water.

They feed mainly on small ants that stick to their skin due to the bumps located on their back which also help them regulate temperature. Reproduction occurs during the warmer months when males seek out females for mating purposes.

The lifespan of this species can reach up to 20 years in captivity but is typically much shorter in the wild due to predation and other natural causes. Despite being listed as least concern by the IUCN Red List, human activity has caused destruction of habitats leading to declines in population numbers across some regions of Australia.

This only emphasizes the importance of conserving these animals and protecting their habitats so future generations may experience such a remarkable species first-hand. By studying the behaviors and ecological requirements of this species, researchers can gain valuable insight into how best we can protect these creatures from extinction while continuing our own development efforts within their range.