The Northland green gecko or Gray's tree gecko (Naultinus grayii ) is a species of gecko, a lizard in the family Gekkonidae. The species is found only in the Northland region of New Zealand, north of Whangaroa; it is one of the rarest and most highly sought after lizards. Taxonomy Naultinus grayii was originally described by Thomas Bell in 1843. Etymology The specific name, grayii, is in honor of British herpetologist John Edward Gray. Description The Northland green gecko is vivid green with grey or gold-coloured markings on either side along the dorsal surface. Males have a blue band along the sides just below the limbs. Underneath, the ventral surface of both sexes is bright pale green, sometimes with a yellow tinge. The inside of the mouth is deep blue with a bright red tongue. Its total length (including tail) is up to , and its snout-to-vent length (SVL) is up to . Behaviour The Northland green gecko is diurnal, often found sun-basking. It has an arboreal lifestyle, especially favouring stands of manuka, kanuka, and mingimingi. Conservation status In 2012 the Department of Conservation classified the Northland green gecko as "At Risk" under the New Zealand Threat Classification System. It was judged as meeting the criteria for "At Risk" threat status as a result of it having a low to high ongoing or predicted decline. This gecko is also regarded as being "Data Poor". Captivity This species, like all the Naultinus species, is regarded as the Holy grail of Geckos among their keepers, often going for a large amount of money for a pair of lizards. Outside of its home range, it is most commonly kept in Europe where there are several keepers producing offspring, though still extremely rarely seen. In 2001 a German tourist was fined $12,000 for attempting to smuggle Northland green geckos out of the country in his underwear. See also Geckos of New Zealand References Further reading Bell T (1843). The Zoology of the Voyage of H.M.S. Beagle Under the Command of Captain Fitzroy, R.N., during the years 1832 to 1836. Edited and Superintended by Charles Darwin ... Naturalist to the Expedition. Part 5., Reptiles. London: Smith, Elder and Company. vi + 51 pp. + Plates 1-20. (Naultinus grayii, new species, pp. 27–28 + Plate 13, figure 2). (in English and Latin). Buller W (1871). "A List of the Lizards inhabiting New Zealand, with Descriptions". Transactions