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| range_map_alt= map of New Zealand showing multicolored area across the country }} ''Naultinus'' is a genus of geckos. It is one of two genera of geckos that are endemic to New Zealand, the other genus being ''Hoplodactylus''. On account of their striking colouration, species in the genus ''Naultinus'' are commonly known as green geckos. There are eight described species in the genus, while another species from the North Island is awaiting formal scientific description. Species in the genus share a number of traits that set them apart as quite different from the rest of the world's two thousand odd gecko species, which are generally brown in colour, ovivaparous, short-lived and nocturnal. In contrast, ''Naultinus'' are green (with the exceptions of males in two South Island species which exhibit sexual dimorphism in colouration), ovovivaparous, live up to 30 years or more and are strictly diurnal. New Zealand has a temperate, maritime climate, and in terms of distribution ''Naultinus'' is one of the southern-most gecko genera in the world — some species live in habitats in the South Island which receive regular snowfall in winter. Animals in this genus possess several physiological and behavioural adaptations to cope with these periods of low temperatures and adverse weather. While historically widespread and quite common in areas of native forest all over the country, all species in this genus are of conservation concern in the present day. All nine species of ''Naultinus'' are declining in the wild and are much harder to find than they used to be; the populations of the various species are highly fragmented and approaching extinction, while others in the genus have already gone extinct. Entire populations of certain species, with unique traits and distinctive genetic profiles, have disappeared in the last 20 years. The primary known agents of this catastrophic decline include predation by invasive mammalian and avian species, habitat destruction and poaching for the illegal pet trade. Vespid wasp predation is speculated to be another possible contributing cause. Legal protection in the form of longer prison sentences for poachers caught with New Zealand protected species has been increased in recent years and translocations of various species to pest free islands have been undertaken with mixed results, but the task of saving these animals remains daunting. The behavioural and visually cryptic nature of these animals also pose challenges to their conservation management. The genus is, in general, in "dire need of research, particularly into factors that are causing their apparent decline", certain aspects of which remain unexplained.〔 ==Description== ''Naultinus'' species are commonly known as "green geckos" in New Zealand for their striking bright green colouration. In addition, they are diurnal, which allows them to take advantage of warmer day-time temperatures.〔 Both of these features are shared only with the day geckos (''Phelsuma'') of Madagascar. Almost every other type of gecko in the world is nocturnal and brown or grey in colour.〔 All ''Naultinus'' are arboreal, and though most of them are predominantly green, their skin patterns are known to be plain (''N. manukanus'', '' N. punctatus''), spotted (''N. elegans'', ''N. gemmeus'', ''N. grayii'', ''N. punctatus'', ''N. rudis'', ''N. stellatus'', ''N. tuberculatus''), or striped (''N. gemmeus''). Occasionally, individuals of an overall lemon-yellow colour are encountered; this is a rare genetic colour morph similar to albinism. The distinctive green colouration is almost universally predominant; with the two exceptions of male ''N. rudis'' as well as males of some populations of the Canterbury form of ''N. gemmeus'', which are sexually dichromatic.〔 While females are green, the males of ''N. rudis'' are grey with white and brown splotches, and in Canterbury, ''N. gemmeus'' females are always predominantly green as compared to the grey, brown or white males.〔 The inside of the mouth, which is revealed in a threat display in some species, is deep blue, orange, pink or red.〔 The broad fleshy tongue, which has a major function in cleaning the transparent scales which cover the eyes, is also brightly coloured; depending on the species it is red, orange, pink, yellow or black.〔 The ears of New Zealand geckos appear as small openings on the side of the head behind the eyes, and the eardrum is visible a short distance inside this opening.〔 ''Naultinus'' species and indeed, New Zealand lizards in general, are very conservative in their evolutionary development of scales.〔 Most have the standard gecko-type scales which are small and granular, giving the skin a dull, velvety appearance. The two exceptions to this rule are two South Island members of the genus; the rough gecko (''N. rudis'') and, to a lesser extent, the Marlborough green gecko (''N. manukanus''). The rough gecko has enlarged conical scales which are both significantly wider and which protrude much further from the body than ordinary scales. These enlarged scales are scattered all over the body except for the underside of the animal.〔 The Marlborough green gecko also has enlarged scales, but they are confined to the dorsal, pelvic area, and sometimes even in rows along the side of the animal. In any case, they are never found over all upper surfaces of the body as in the rough gecko.〔 All ''Naultinus'' species also possess very long, finely tapered, strongly prehensile tails which they use as a "fifth limb" for grasping when they climb among the twigs and leaves of their arboreal habitat.〔 They can hang by their tails if necessary.〔 They also have comparatively slender toes, another adaptation to their arboreal lifestyle.〔 The arboreal ''Naultinus'' use their toes in a grasping action on twigs and leaves, but there is some lamellar function as well.〔 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「Naultinus」の詳細全文を読む スポンサード リンク
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