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A goanna is any of several Australian monitor lizards of the genus ''Varanus'', as well as to certain species from Southeast Asia. Around 30 species of goanna are known, 25 of which are found in Australia. This varied group of carnivorous reptiles ranges greatly in size and fills several ecological niches.〔Ehmann, Harald. ''Encyclopedia of Australian Animals: Reptiles''. (1992), p. 144. Angus&Robertson, Pymble, Australia. ISBN 0-207-17379-6.〕 The goanna features prominently in Aboriginal mythology and Australian folklore. Being predatory lizards, goannas are often quite large, or at least bulky, with sharp teeth and claws. The largest is the perentie (''V. giganteus''), which can grow over in length. Not all goannas are gargantuan. Pygmy goannas may be smaller than a man's arm. The smallest of these, the short-tailed monitor (''Varanus brevicuda'') reaches only 20 cm in length. They survive on smaller prey, such as insects and mice. Goannas combine predatory and scavenging behaviours. A goanna will prey on any animal it can catch and is small enough to eat whole. Goannas have been blamed for the death of sheep by farmers, though most likely erroneously, as goannas are also eaters of carrion and are attracted to rotting meat. Most goannas are darkly coloured, with greys, browns, blacks and greens featuring prominently; however, white is also common. Many desert-dwelling species also feature yellow-red tones. Camouflage ranges from bands and stripes to splotches, speckles, and circles, and can change as the creature matures, with juveniles sometimes being brighter than adults. Like most lizards, goannas lay eggs. Most lay eggs in a nest or burrow, but some species lay their eggs inside termite mounds. This offers protection and incubation; additionally, the termites may provide a meal for the young as they hatch. Unlike some other species of lizards, goannas do not have the ability to regrow limbs or tails. ==Habitats== Goannas are found throughout most of Australia, except for Tasmania, and manage to persist in a variety of environments. Most species are known to climb trees or outcrops; several primarily arboreal species are known. The lace monitor (''V. varius'') is probably the best-known amongst these, but is not the most common. The lace monitor is the second-largest of all goannas, reaching lengths of up to 2 m. Other more common tree goannas, such as the Timor tree monitor (''V. timorensis'') and mournful tree monitor (''V. tristis'',) do not grow to quite such lengths, averaging only a few feet nose-to-tail. Other goannas are adapted to swampy coastal environments, such as the mangrove goanna (''V. semiremex''). Further still, the Mertens' water monitor (water goanna – ''V. mertensi''), found in lagoons and rivers across northern Australia, is streamlined for swimming, using its tail as a paddle. Most other goannas are good swimmers, but tend not to voluntarily venture into the water. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Goanna」の詳細全文を読む スポンサード リンク
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