Blue-tongued skink

Blue-tongued skink
Stump-tailed skink, Tiliqua rugosa
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia (paraphyletic)
(unranked):	Sauria
Order:	Squamata (paraphyletic)
Infraorder:	Scincomorpha
Family:	Scincidae
Subfamily:	Lygosominae
Genus:	Tiliqua
Species
7, see text.
Synonyms
Trachydosaurus

Blue-tongued skinks are the genus Tiliqua, which contains some of the largest members of the skink family (Scincidae). They are called commonly blue-tongued lizards in Australia, where true lizards (Lacertidae) do not naturally occur. As suggested by these common names, its distinguishing characteristic is a blue tongue.

Systematics

Like their close relatives of the genus Cyclodomorphus, the blue-tongues belong to the Egernia group (Austin & Arnold 2006). There are six species of blue-tongues which occur in Australia. A distinct species, Tiliqua gigas, occurs in various areas of Indonesia, particularly the island of New Guinea. One of the 3 subspecies of Tiliqua scincoides is found on several small Indonesian islands between Australia and New Guinea. Most species, with the exception of the pygmy blue-tongue, are relatively large (27-60 cm total length), heavy-bodied, short-limbed, broad with a distinct head, and short, tapered tail.

• Tiliqua adelaidensis, Pygmy Blue-Tongued Skink
• Tiliqua gigas, Indonesian Blue-Tongued Skink
• Tiliqua multifasciata, Central Blue-Tongued Skink
• Tiliqua nigrolutea, Blotched Blue-Tongued Skink
• Tiliqua occipitalis, Western Blue-Tongued Skink
• Tiliqua rugosa, Stump-tailed Skink or Shingleback Skink
• Tiliqua scincoides, Common Blue-Tongued Skink
  • Tiliqua scincoides scincoides, Eastern Blue-Tongued Skink
  • Tiliqua scincoides intermedia, Northern Blue-Tongued Skink
  • Tiliqua scincoides chimaerea, Tanimbar Blue-Tongued Skink

• 
  Western blue-tongued skink
• 
  Central blue-tongued skink from the Tanami Desert
• 
  Eastern Blue-Tongued Skink

Ecology

These lizards occupy a range of habitats from desert, semi-arid savannah, woodland and temperate suburban areas through to tropical jungle. They are omnivorous, and may feed on berries, flowers and other plant material, fungi, insects, spiders, or other small animals, carrion, and are very partial to snails and slugs. They may grow up to 60 cm (depending on the species). Solitary for most of the year, mating occurs in September-November. Pair bonding may occur over successive years (Bull 1988, 1990). The young are born (live) 3-5 months after mating (December-April). Litters may have 5-18 individuals.

Predators include kookaburras, raptors, and snakes such as the Eastern brown snake or the Mulga snake (Valentic 1996). Dogs and cats have also been known to attack bluetongues in a suburban environment. When a blue-tongue is threatened it will face the threat opening its mouth wide, sticking out its blue tongue in an attempt to scare away the threat.

References

• Austin, J.J. & Arnold, E.N. (2006): Using ancient and recent DNA to explore relationships of extinct and endangered Leiolopisma skinks (Reptilia: Scincidae) in the Mascarene islands. Molecular Phylogenetics and Evolution 39(2): 503–511. doi:10.1016/j.ympev.2005.12.011 (HTML abstract)
• Bull, C.M. (1988): Mate fidelity in an Australian lizard Trachydosaurus rugosus (Scincidae). Copeia 1987(3): 749-757.
• Bull, C.M. (1990): Comparison of displaced and retained partners in a monogamous lizard Tiliqua rugosa. Australian Wildlife Research 17: 135-140.
• Valentic, R.A. (1996): A prey record of the Eastern Blue-tongue Tiliqua scincoides for the common brown snake Pseudonaja textilis. Monitor 8(3): 155.