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The green and golden bell frog (''Litoria aurea''), also named the green bell frog, green and golden swamp frog and green frog, is a ground-dwelling tree frog native to eastern Australia. Despite its classification and climbing abilities, it does not live in trees and spends almost all of its time close to ground level. It can reach up to 11 cm (4.3 in) in length, making it one of Australia's largest frogs. Coloured gold and green, the frogs are voracious eaters of insects, but will also eat larger prey, such as worms and mice. Unlike most frogs, they are active at day, although this is mostly to warm in the sun. They tend to be less active in winter except in warmer or wetter periods, and breed in the warmer months. Males reach maturity after around 9 months, while for the larger females, this does not occur until they are two years old. The frogs can engage in cannibalism, and males frequently attack and injure one another if they infringe on one another's space. Many populations, particularly in the Sydney region, inhabit areas of infrequent disturbance, such as golf courses, disused industrial land, brick pits, and landfill areas. Though once one of the most common frogs in south-east Australia, the green and golden bell frog has endured major population declines, particularly in highland areas, leading to its current classification as globally vulnerable. Its numbers have continued to fall and are threatened by habitat loss and degradation, pollution, introduced species, and parasites and pathogens, including the chytrid ''Batrachochytrium dendrobatidis''.〔(【引用サイトリンク】 url=http://www.iucnredlist.org/search/details.php/12143/all )〕 As most of the remaining populations live on private land, the logistics of the conservation effort can be complicated. Despite the situation in Australia, the frog remains abundant in New Zealand and several other Pacific islands, where it has been introduced. ==Taxonomy== The common name, "green and golden bell frog", was first adopted by Harold Cogger in his 1975 book ''Reptiles and Amphibians of Australia''. Before this, its common names were "golden frog" and "golden tree frog". The green and golden bell frog has many physical and behavioural characteristics representative of ranids, hence its original classification as ''Rana''. It has a pointy snout, long legs, and almost complete toe webbing; the tympanum is large and distinct; and the overall body shape is similar to many ''Rana'' species. Like many frogs in the ''Rana'' genus, green and golden bell frogs are mostly aquatic, and only travel over land during periods of rainfall. It was removed from the genus because of anatomical differences with the family Ranidae. The bone and cartilage structural formations of the green and golden bell frog are closest to those of species in the family Hylidae; it was therefore reclassified. The green and golden bell frog was first described as ''Rana aurea'' by Lesson in 1827. It has changed classification 20 times; it was first named ''Litoria aurea'' in 1844 by Günther, and changed another 9 times before being named again as ''Litoria aurea''.〔(【引用サイトリンク】 url=http://research.amnh.org/herpetology/amphibia/references.php?id=6077 )〕 The specific epithet ''aurea'' derived from the Latin ''aureus'' for 'golden'. The species is now classified within the ''Litoria aurea'' complex, a closely related group of frogs in the ''Litoria'' genus.〔Mahony, p. 82.〕 This complex is scattered throughout Australia: three species occur in south-east Australia, one in northern Australia, and two in Southwest Australia.〔 The complex consists of the green and golden bell frog (''L. aurea''), growling grass frog (''L. raniformis''), yellow-spotted bell frog (''L. castanea''), Dahl's aquatic frog (''L. dahlii''), spotted-thighed frog (''L. cyclorhyncha'') and the motorbike frog (''L. moorei'').〔 The ranges of ''L. raniformis'' and ''L. castanea'' overlap with the green and golden bell frog;〔 this, as well as physical similarities, may make it difficult to distinguish between the species, and until 1972, ''L. raniformis'' and the green and golden bell frog were regarded as the same, when electrophoretic studies proved them to be distinct.〔 The tablelands bell frog has not been seen since 1980 and may now be extinct, although the large yellow spots present on its thighs help distinguish it from the green and golden bell frog. The growling grass frog, which is very similar to the green and golden bell frog, can only be readily distinguished by raised bumps on the dorsal surface. It has also been proposed that some populations of ''L. aurea'' located near Ulong, New South Wales, be a separate subspecies, ''L. a. ulongae'', but this was not accepted.〔Pyke and White, p. 568.〕 ''Litorea aurea'' is equally and most closely related to ''Li. castanes'' and ''L. ranaformis''. A microcomplement fixation technique using serum albumins has indicated the species closest to ''L. aurea'' is ''L. ranifomis''. Albumin immunological distance data suggest no differentiation between the two, and the green and golden bell frog evolutionally separated from the other two species about 1.1 million years ago. A 1995 study of protein variations showed four of 19 protein systems had variation and only two had differentiation.〔 Scientists believe the different species can still hybridise, as their distribution areas still overlap, and both ''L. raniformis'' and ''L. aurea'' have been seen sharing ponds in the Gippsland area of Victoria.〔 However, little evidence of hybridisation actually occurring has been found. Although there have been reports of frogs of mixed appearance in Gippsland, analysis of proteins and sera of the frogs showed two distinct species.〔 Samples in other area of distribution have shown no evidence of hybridisation in spite of cohabitation.〔Pyke and White, p. 569.〕 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「Green and golden bell frog」の詳細全文を読む スポンサード リンク
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