Burton’s legless lizard (Lialis burtonis)

Also known as: Burton's snake-lizard
Synonyms: Lialis bicatenata, Lialis burtoni, Lialis burtonii, Lialis leptorhyncha, Lialis punctulata
KingdomAnimalia
PhylumChordata
ClassReptilia
OrderSauria
FamilyPygopodidae
GenusLialis (1)
SizeSnout-vent length: up to 29 cm (2) (3)
Total length: up to 75 cm (4)
Top facts

Burton’s legless lizard has yet to be classified on the IUCN Red List.

One of Australia’s most common species (3), Burton’s legless lizard (Lialis burtoni) is a limbless (4), snake-like lizard (5) (6), and is one of the largest members of the Pygopodidae family (6) (7). Pygopodids are also known as ‘flap-footed lizards’ (6), and are so named because of the two tiny, scaly flaps which are all that remain of the hind limbs (2) (6) (8) (9). It is thought that these legless lizards evolved their long-bodied, near-limbless shape to move through dense, low vegetation (6).

A stout-bodied, large-eyed species (3), Burton’s legless lizard can be distinguished from snakes and other legless lizards by its long, distinctive, wedge-shaped snout (2) (3) (7) (8). Unlike in snakes, its tail is longer than its body (8), making up two-thirds of the reptile’s total length (9). Burton’s legless lizard has conspicuous ear openings (8), and the paired scales on its underside are noticeably wider than the adjacent body scales (2).

Arguably one of Australia’s most variable lizards (6), Burton’s legless lizard can be found in an astonishing array of colour forms (2) (6), with the body ranging from pale grey to brown, red or yellow. Individuals may be plain and uniformly coloured, or patterns such as black dashes or prominent stripes may be present (2) (3) (8). A dark lateral line can often be seen extending from the eye region along the front part of the body (8).

While colour and markings generally vary within populations of Burton’s legless lizard (8), in some regions it appears that environmental factors may influence patterning. Greater numbers of striped individuals are found in spinifex grasslands, while paler individuals with broad black and white facial stripes are often found in northern woodland areas (2). Female Burton’s legless lizards are known to be noticeably larger than the males (8).

Australia’s most widespread lizard (6), Burton’s legless lizard is found in all six of the country’s mainland states (1) (2) (4), as well as in southern New Guinea (2) (6) and parts of Indonesia, including southern Irian Jaya and the Aru Islands (1) (4).

Like other pygopodid species, Burton’s legless lizard prefers relatively dry habitats, often with a ground cover of spinifex, heath, thick tussock grass or leaf litter, and with an open canopy (6). Such habitats include shrublands with rocky outcrops, dry open forest and woodland (10), heathland and grassland (8).

Areas with surface rocks and fallen timber to hide under are preferable, as are habitats with a well-established leaf-litter layer (3) (10). Burton’s legless lizard can also often be found sheltering under sheets of iron or other bits of human refuse (8). While pygopodids are not generally seen out in the open, Burton’s legless lizard can often be sighted crossing roads and sandy tracks (6).

Burton’s legless lizard is mainly a crepuscular species (10), but is also known to sometimes be active at night in warm weather, and during the day in overcast conditions (2) (3) (10). This species’ vertical pupils give it good vision at night, as the pupils can open more rapidly than round ones, and have maximum expansion in low light conditions (6).

A terrestrial species, Burton’s legless lizard worms its way through dense grass tussocks and under small shrubs and fallen timber (9) (10), and is sometimes mistakenly called a ‘grass snake’ (9). This species holds its head and neck in a distinctive elevated posture when at rest or basking, maintaining an angle of about 45 degrees to the ground. If attacked by a predator, Burton’s legless lizard can be surprisingly vocal, producing loud squeaks, and its fragile tail may be easily shed as a defence mechanism (10).

Legless lizards are generally insectivorous, but Burton’s legless lizard is an unusual exception to this rule (7). This species is a lizard specialist (5) (6) (8), feeding exclusively on reptiles (2). While Burton’s legless lizard demonstrates a preference for skinks (9) (10) (11), a group which forms 95 percent of its diet (6), it also preys on other lizards (2) (7), including geckos, dragons and other legless lizard species (8) (10). There have even been reports of this unusual reptile preying upon certain snake species (6) (10).

Burton’s legless lizard is an ambush predator (2) (6) (10), lying in wait for its victim, concealed among thick, low vegetation (6). Prey is snatched via a sideways swipe of the legless lizard’s wedge-shaped snout, and is gripped tightly around the chest and suffocated (2) (10). Interestingly, Burton’s legless lizard has a special adaptation which enables it to do this. This species has a uniquely hinged skull, with an unusual hinge across the head, roughly at eye-level (2) (6), which provides greater mobility. This allows the upper and lower jaws to completely encircle the prey and meet at the tip (3) (5) (6).

The prey is firmly held in place by fine, backward-pointing teeth (3) (6), which are also hinged and lock into place when pressured from behind (6). Once the prey has been suffocated, it is then manipulated by flexing the skull to force the victim head-first down the lizard’s throat (6) (10), and is swallowed whole (5). These special adaptations enable Burton’s legless lizard to eat lizards that are particularly large relative to its own size (6).

Mating in Burton’s legless lizard occurs in the spring (10), with pregnant females being found from September to February (8). As in other flap-footed lizard species, Burton’s legless lizard is thought to lay a clutch of two, flexible-shelled eggs (6) (10), which are deposited under a rock or a log (10). Communal nests have been documented in this species, with a record of 20 eggs per nest (6) (8), and it is thought that Burton’s legless lizard may lay more than one clutch per breeding season (8).

At present, Burton’s legless lizard is not known to be facing any major threats.

Although Burton’s legless lizard is not currently thought to be at risk of extinction, proposed habitat management measures to support this intriguing reptile include leaving surface rocks, fallen timber and dead trees in place (3).

Find out more about the conservation of Australian reptiles:

Learn more about reptile species on Barrow Island:

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This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:
arkive@wildscreen.org.uk

  1. Species 2000 and ITIS Catalogue of Life (December, 2012)
    http://www.catalogueoflife.org/col/details/species/id/4462910
  2. Wilson, S. (2005) A Field Guide to Reptiles of Queensland. New Holland Publishers, Australia.
  3. Michael, D. and Lindenmayer, D. (2010) Reptiles of the NSW Murray Catchment: A Guide to their Identification, Ecology and Conservation. CSIRO Publishing, Collingwood, Australia.
  4. The Reptile Database (December, 2012)
    http://reptile-database.reptarium.cz/search.php
  5. Pianka, E.R. and Vitt, L.J. (2006) Lizards: Windows to the Evolution of Diversity. University of California Press, California.
  6. Wilson, S.K. (2012) Australian Lizards: A Natural History. CSIRO Publishing, Collingwood, Australia.
  7. Watharow, S. (2011) Living with Snakes and Other Reptiles. CSIRO Publishing, Collingwood, Australia.
  8. Swan, M. and Watharow, S. (2005) Snakes, Lizards and Frogs of the Victorian Mallee. CSIRO Publishing, Collingwood, Australia.
  9. Burton, M. and Burton, R. (2002) International Wildlife Encyclopedia Set. Marshall Cavendish, New York.
  10. Tzaros, C. (2005) Wildlife of the Box-Ironbark Country. CSIRO Publishing, Collingwood, Australia.
  11. Reilly, S.M., McBrayer, L.B. and Miles, D.B. (Eds.) (2007) Lizard Ecology. Cambridge University Press, Cambridge.