Eastern hooded scaly-foot

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Eastern hooded scaly-foot
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Squamata
Family: Pygopodidae
Genus: Pygopus
Species:
P. schraderi
Binomial name
Pygopus schraderi
Boulenger, 1913

The eastern hooded scaly-foot or eastern scaly-foot (Pygopus schraderi) is a species of flap-footed lizard found in the complex heaths of the lower west coast and the spinifex grasslands of mainland Australia. [2] They are popular pets and are often mistaken for snakes due to their limbless appearance. [2] [3]

Contents

Taxonomy

Family Pygopodidae

The family of Pygopods consists of 41 described species found only in Australia and New Guinea. [4] [5] [2] They inhabit most of mainland Australia except for south-eastern Victoria and Tasmania, preferring dry open habitats. [4] [5] [2]

Pygopods, or ‘legless lizards’, move by lateral undulations of the body and tail. [4] [6] They have no forelimbs but have retained vestigial hind limbs in the form of small scaly flaps that are usually held flat on either side of the body. [4] [5] [2]

Pygopods can further be distinguished from snakes by their broad fleshy tongues, ear-openings (which snakes lack), and long tails, which grow up to four times the length of the body and can be voluntarily broken off. [4] [5] [6] [2] Pygopods also have scales on their belly that are the same size as adjacent scales and larger scales that are in a paired series. [4] [2] By contrast, most snakes have one series of enlarged, transverse ventral scales. [4] [2]

Despite their snake-like appearance, the closest relatives of Pygopods are geckos. [7] [8] [6] [2] The relationship is so close that there is growing agreement that the families are actually one and the same. [7] [6] [8] [2] Shared characteristics between the two groups include: a similar skull and inner ear, the sharing of a voice in the form of a ‘squeak’ and both species lay parchment-shelled eggs in clutch sizes of two. [7] [6] [2] Both species also share the ability to lick clean the clear spectacles covering their lidless eyes. [7] [6] [2]

Genus Pygopus

Five species fall under the genus Pygopus; the common scaly-foot (Pygopus lepidopodus), the western hooded scaly-foot (Pygopus nigriceps), Roberts’ scaly-foot (Pygopus robertsi), the eastern hooded scaly-foot (Pygopus schraderi), and the northern hooded scaly-foot (Pygopus steelescotti). [7] [4] [6] [2] All four species are large and robust, with round snouts and prominent ear-openings. [4] [2] They have smooth to keeled scales in 21 or more rows, enlarged paired ventrals, long tails and very large, well-developed limb-flaps. [4] [2] The identification between the species can often be determined by the presence or extent of dorsal keels and whether the nostril contracts at the 1st upper labial scale or is separated. [4] [6] [2]

Common names

Pygopods are also referred to as snake lizards and flap-footed lizards. [4] [6] [2]

Etymology

The species common name comes from the dark symmetrical scales on top of the lizard’s head which give it a "hooded appearance". [4] [2]

The specific name, schraderi, is not in honor of Carl Wilhelm Otto Schrader, the German explorer and naturalist. [9] Boulenger (1913) does not give a specific etymology, but notes that the holotype was from the collection of a Mr. P. Schrader, after whom he presumably named the species. [9]

Description

The eastern hooded scaly-foot is the second smallest species in the genus Pygopus. [4] [2] It has a snout-vent length of 198mm but can grow to lengths of up to 475mm, with females growing larger than males. [2] [10] Their tails alone account for more than three-quarters of their total body length. [8] However, they will readily shed their tails when threatened and are capable of re-growing their tails so at times their tail may be shorter than their body. [4] [5] [8] A re-growing tail is indicated by an abrupt change in pattern and scale arrangement. [8]

Distribution Map for the Eastern Hooded Scaly-foot (Pygopus schraderi) Distribution Map for the Eastern Hooded Scaly-foot (Pygopus schraderi).jpg
Distribution Map for the Eastern Hooded Scaly-foot (Pygopus schraderi)

The markings on these lizards range from reddish-brown to pale grey on the upper body, with a whitish colour underneath. [8] [2] [10] Dark brown to black symmetrical scales on top of the lizard’s head give it a ‘hooded appearance’. [8] [2] [10] These head markings closely resemble those of young brown snakes (Pseudonaja spp.), although it is not known whether this is due to direct mimicry or whether the pattern helps to regulate temperature. [8] [2] The body scales may be dark-edged, forming on overall reticulated or net-like pattern. [8] [2] [10] Individual paler and darker scales may form distinct but irregular V-shaped cross-bands or sometimes broken longitudinal lines or stripes, especially on the flanks. [8] [2] [10] All of these markings as still present, but sometimes only faintly in larger individuals. [8] [2] [10] Its scales are keeled, with body scales in 21-25 rows (including ventrals) at mid-body. [2] The eastern hooded scaly-foot has fewer than 120 ventral scales that are noticeably wider than adjacent body scales and its nostril contracts at the 1st upper labial scale. [2]

Distribution and habitat

The eastern hooded scaly-foot is found in inland New South Wales, Victoria, eastern South Australia, inland Queensland and adjacent parts of the Northern Territory. [8] [2] [11] [10] It is found in dry to arid zones in a variety of open habitats ranging from stony plains and dry woodlands to arid mallee, mulga scrubs and spinifex-dominate desert grasslands. [8] [2] [11] [10] It prefers stony and heavy soils and is dependent on large, interconnected territories. [8] [2] [11] [10] Due to its inability to sustain or rapidly recover from aerobic activity, this species will shelter in soil cracks, grass and under debris, as well as large burrows to avoid predation. [8] [2] [11] [10]

In NSW, the hooded scaly-foot is rare in the NSW Murray Catchment, but is found in areas supporting native grasslands and grassy woodlands, especially in the region bordering the Murrumbidgee Catchment in the north. [11]

Within Victoria, the hooded scaly-foot is rarely encountered and is known to exist at only six sites including Terrick Terrick National Park, Korrack Korrack grasslands and areas west of Mildura such as Lake Ranfurly and Neds Corner Station. [10]

Behaviour

Not a lot is known about the ecology of the eastern hooded scaly-foot, however research has shown that is primarily nocturnal, although populations in southern Victoria have been observed to be active during the day. [10] They are also thought to be inactive during winter. [10] Although usually encountered singly, occasional aggregations have been reported, possibly related to breeding [12] [4]

Snake mimicry is an important part of this species’ survival strategy. [4] To deter predators, the eastern hooded scaly-foot will rear and flicker its tongue in apparent mimicry of venomous snakes. [4] [2] Unfortunately, this behaviour is so impressive that this harmless species is often mistaken for a venomous snake and killed. [4] [5] [2] When grasped, they struggle fiercely, rotating their bodies and uttering long harsh squeaking sounds. [4] [2] These sounds are also emitted occasionally during social interactions. [4] [2]

The eastern hooded scaly-foot has been observed to excavate tunnels in soft soil by removing soil with the mouth and rotating the body to widen the tunnel. [4] Such tunnelling behaviour may allow the animal access to insects, on which it feeds. [4]

Captive scaly-foots have been recorded to live for up to 7 years. [3] However, little is known about ages of individuals on the wild. [3]

Predators

Predators of the eastern hooded scaly-foot include raptors, goannas, feral cats, foxes and elapid snakes. [10]

Hunting and diet

The eastern hooded scaly-foot is a hypo-metabolic (low energy) specialist that requires minimal amounts of food and water. [13] [12] They feed predominantly on surface-active arthropods such as spiders; but they also feed on spider egg sacks and scorpions. [12] [2] [10] This species has been observed to actively search for prey. [10] Once caught, prey is disabled and crushed as the hooded scaly-foot rapidly rotates its body along the long axis. [12] [13] [4] Dentition is pleurodont, with the teeth blunt and rounded, and firmly attached to the bone. [7] [12]

Reproduction

The eastern hooded scaly-foot is oviparous and lays a clutch of two eggs (occasionally one or three) once a year in spring or early summer with breeding occurring from August to March. [12] [4] [2] Pregnant females have been reported in January and February and incubation periods range from 66 to 77 days. [2] [10] Pygopus species have been noted to lay communally. [4] [5]

In captivity, few courtship or mating displays have been observed. [3] Males will follow the female while flicking their tongue repeatedly. [3] Pelvic spurs, modified spine-like scales and hind-limb ‘flaps’ on males are thought to assist the male in gripping the female. [7] [3]

Captivity

Pygopods are easy to maintain in captivity and are highly sought after. [3] However, they are rarely available due to their unpredictable breeding performance. [3] A license is required before this species can be kept as a pet in Australia. [3]

Conservation

The eastern hooded scaly-foot has not yet been assessed for the IUCN Red List but it is listed as ‘threatened’ under the Flora and Fauna Guarantee Act 1988 and is classified as ‘critically endangered’ in Victoria under the Department of Sustainability and Environment’s Advisory List of Threatened Fauna. [2] [10] Threats to the eastern hooded scaly-foot include:

In Victoria, the Mallee CMA is undertaking a number of monitoring based projects to help address knowledge gaps for the eastern hooded scaly-foot. [10] The Mallee CMA aims to:

Related Research Articles

<span class="mw-page-title-main">Lizard</span> Informal group of reptiles

Lizards are a widespread group of squamate reptiles, with over 7,000 species, ranging across all continents except Antarctica, as well as most oceanic island chains. The group is paraphyletic since it excludes the snakes and Amphisbaenia although some lizards are more closely related to these two excluded groups than they are to other lizards. Lizards range in size from chameleons and geckos a few centimeters long to the 3-meter-long Komodo dragon.

<span class="mw-page-title-main">Pygopodidae</span> Family of lizards

Pygopodidae, commonly known as legless lizards, snake-lizards, or flap-footed lizards, is a family of squamates with reduced or absent limbs, and are a type of gecko. At least 35 species are placed in two subfamilies and eight genera. They have unusually long, slender bodies, giving them a strong resemblance to snakes. Like snakes and most geckos, they have no eyelids, but unlike snakes, they have external ear holes and flat, unforked tongues. They are native to Australia and New Guinea.

<i>Pygopus</i> Genus of lizards

Pygopus is a genus belonging to the family of Australian legless lizards (Pygopodidae). Members of this genus are also commonly called scaly-foot.

<span class="mw-page-title-main">Tiger snake</span> Highly venomous snake native to southern Australia and Tasmania

Tiger snakes are a large and highly venomous snake of southern Australia, including its coastal islands and Tasmania. These snakes are often observed and locally well known by their banding, black and yellow like a tiger, although the species can be highly variable in coloration and patterning. All populations are classified within the genus Notechis (Elapidae). Their diverse characteristics have been classified either as distinct species or by subspecies and regional variation.

<span class="mw-page-title-main">Legless lizard</span> Common name for a lizard without obvious legs

Legless lizard may refer to any of several groups of lizards that have independently lost limbs or reduced them to the point of being of no use in locomotion. It is the common name for the family Pygopodidae. These lizards are often distinguishable from snakes on the basis of one or more of the following characteristics: possessing eyelids, possessing external ear openings, lack of broad belly scales, notched rather than forked tongue, having two more-or-less-equal lungs, and/or having a very long tail.

<span class="mw-page-title-main">Brigalow scaly-foot</span> Species of lizard

Paradelma orientalis, commonly known as the Brigalow scaly-foot or Queensland snake-lizard, is a species of legless lizard in the family Pygopodidae. It is endemic to Australia and is the only species in the monotypic genus Paradelma.

<span class="mw-page-title-main">Burton's legless lizard</span> Species of lizard

Burton's legless lizard is a species of lizard in the family Pygopodidae. The species lacks forelegs and has only rudimentary hind legs. Pygopodid lizards are also referred to as "legless lizards", "flap-footed lizards" and "snake-lizards". This species is native to Australia and Papua New Guinea.

<i>Eulamprus quoyii</i> Species of lizard

Eulamprus quoyii, more commonly known as the eastern water skink, eastern water-skink, or golden water skink, is a viviparous species of diurnal skink. Eulamprus quoyii belongs to the family Scincidae and is considered a common garden animal in Australia. The skink is endemic to Australia and found only along the east coast of the country. It makes its home in creekside habitats along the east coast of Australia and in urban garden areas with high amounts of moisture. The species can be identified by the twin, long yellow stripes that run along its body from the top of the eye, as well as by several more specific character derived states. The pale yellow dorsolateral stripes are most likely where its common name, the golden water skink, is derived. Like other ectotherms, the skink can often be seen basking in the sun on rocky outcroppings in order to regulate its body temperature. Its diet mainly consists of both aquatic and terrestrial insects, tadpoles and small amounts of plant matter. The skink both hunts for food and scavenges when necessary and is considered an opportunistic feeder. It is prey to larger lizards, snakes, cats and birds and so will often be seen moving quickly into hiding when other organisms are present.

<span class="mw-page-title-main">Common scaly-foot</span> Species of lizard

The common scaly-foot is a widespread species of legless lizard in the Pygopodidae family. It is endemic to Australia.

<span class="mw-page-title-main">Curl snake</span> Species of snake

The curl snake is a species of venomous, heavily built snake in the family Elapidae. The species, which is native to Australia, is also known more commonly in Western Australia as the myall snake. The curl snake is often confused with a similar species named the Ord curl snake.

<span class="mw-page-title-main">Hooded scaly-foot</span> Species of lizard

The hooded scaly-foot, also known as western scaly-foot, black-headed scaly-foot or western hooded scaly-foot, is an endemic Australian legless lizard of the family Pygopodidae.

<i>Cryptoblepharus australis</i> Species of lizard

Cryptoblepharus australis, commonly called the inland snake-eyed skink, is a species of skink in the genus Cryptoblepharus.

<span class="mw-page-title-main">Pink-tailed worm-lizard</span> Species of lizard

The pink-tailed worm-lizard or granite worm-lizard is a rare legless lizard found in Australia. The animal looks like a combination of small snake and worm. Its total length is up to 14 cm. It has a pink tail and is white underneath. The head and neck are brown, and the rest of the top of the body is pale grey. Scales on the back each have a dark bar, giving the appearance of dots down the back. It is found on two hills near Tarcutta, Bathurst, New South Wales, Bendigo in Victoria, and along the sides of the Molonglo River and Murrumbidgee River and on Mount Taylor in the Australian Capital Territory. The lizards eat invertebrates that live under rocks. They can be found under rocks sized from 0.15 to 0.6 m. Their main diet is ant eggs, particularly from Iridomyrmex species and Rhytidoponera metallica.

Ctenophorus mckenziei, more commonly known as the dwarf-bicycle dragon, is a species of endemic Australian lizard within the family Agamidae and genus Ctenophorus. Originally identified as the agamid Amphibolurus mckenziei, the lizard had been identified within the regions of Western Australia and South Australia in which it occupied the shrubbery and woodland areas as its habitat. It was subsequently transferred to the genus Ctenophorus along with other Agamid species in which it shared similar morphology and characteristics. The name mckenziei is in reference to Norman Leslie Mckenzie, who was a zoologist and discovered the existence of the lizard. Listed on the IUCN red list page, threats to its population numbers are evaluated as least concern; however, their numbers are threatened by habitat loss, climate change, and feral predators.

The northern hooded scaly-foot is a species of legless lizard in the family Pygopodidae. The species is native to northern Australia.

Pygopus robertsi, also known as Robert's scaly-foot or Cape York scaly-foot, is a species of legless lizard of the Pygopodidae family. It is endemic to Queensland, Australia.

<span class="mw-page-title-main">Pygopodoidea</span> Superfamily of lizards

Pygopodoidea is a gecko superfamily and the only taxon in the gekkotan subclade Pygopodomorpha. The clade includes three Australasian families: Diplodactylidae, Carphodactylidae, and Pygopodidae. Traditional gekkotan systematics had considered Diplodactylidae and Carphodactylidae as subfamilies of the family Gekkonidae, but recent molecular work have placed Pygopodidae within Gekkonidae making it paraphyletic. These analyses have shown support of Pygopodidae and Carphodactylidae being sister taxa, with Diplodactylidae occupying a basal position in Pygopodoidea.

<span class="mw-page-title-main">Patternless delma</span> Australian Lizard species

The patternless delma is a species of legless gecko from the Pygopodidae family. This species is commonly found throughout New South Wales, Queensland and southeastern South Australia, mostly inhabiting areas consisting of dry to temperate southern grasslands and grassy woodlands.

<span class="mw-page-title-main">Zuytdorp worm-lizard</span> Species of lizard

The Zuytdorp worm-lizard, also known commonly as Smith's legless lizard, is a species of lizard in the family Pygopodidae. The species is endemic to Australia.

<span class="mw-page-title-main">Little whip snake</span> Species of snake in Australia

The little whip snake, also known commonly as the whip hooded snake, is a species of venomous snake in the family Elapidae. The species is endemic to Australia.

References

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