Naultinus elegans

Elegant gecko | Moko kākāriki

Naultinus elegans
(Gray, 1842)

Elegant geckos (Auckland). © Nick Harker
Image attribution
Elegant geckos (Auckland). © Nick Harker
Herpetofaunal category
NZ Geckos
Species complex
Conservation Status
At Risk - Declining
Previous scientific names
Naultinus elegans elegans
Common names
Elegant gecko,
Auckland green gecko,
Moko kākāriki.

Length: SVL up to 75mm, with the tail being longer than the body length

Weight: up to 15 grams

Description

A gracile, and often strikingly marked species of green gecko, found in the forested regions of the northern North Island of Aotearoa/New Zealand. Although historically known as the Auckland green gecko, this species has quite a wide distribution (Northland to the central North Island), and thus in order not to mislead, its name was instead changed to the elegant gecko in order to reflect its scientific name, and stunning appearance. 

In general, elegant geckos are characterised by their bright to dark green upper surfaces, which in some individuals are broken up by white, cream, or pinkish markings (either striped, blotched, or a combination of both) with thin yellow, dark green, or black outlines. The sides of the animals are much the same as the upper surfaces, although may be underlined by a thin white stripe. Their mouth may be bordered below by a white stripe which terminates at the opening of the ear. As with most of our green gecko species, the elegant gecko's ventral colour differs between males and females, with females having a green stomach, while males have a blue-tinged stomach. 
Mouth and tongue colour is typically a key feature in distinguishing between North Island Naultinus species, however, the elegant, and barking gecko (Naultinus punctatus) share the combination of a deep blue mouth with a black tongue.
Xanthochromic (yellow) and leucistic (white) individuals are known from wild populations.

Can be differentiated from Northland green (Naultinus grayii) and Aupōuri geckos (Naultinus flavirictus) by a black (versus red) tongue, as well as by a blue (versus lilac/pink) mouth colour for the latter. Elegant geckos are extremely similar in appearance to the barking gecko (Naultinus punctatus), but can typically be differentiated by a combination of size (≤75mm vs. ≤95mm SVL), foot colouration (green vs. yellow), and patterning (often patterned vs. often sparsely patterned). Past hybridisation with the barking gecko (N. punctatus) at the southern extent of their range, may have resulted in a mixing of traits in those populations.

Click here for information on how elegant gecko differ in appearance from other species in the Naultinus group.

Life expectancy

Elegant geckos have been recorded to reach ages of ~25 years in captivity, but are likely to exceed this.

Captive green geckos have frequently been known to live for upwards of 25 years, with some individuals topping the records at 50+ (D. Keal pers. comm 2016). In the wild, green geckos have been recorded as reaching a minimum of ~15 years, although it is likely to be more than this given that the population in question was only monitored from 2009, and those animals are still alive (C. Knox pers. comm 2021). 

Distribution

Northern North Island from just south of the Bay of Islands, through to Taranaki, and the Bay of Plenty (north of the Whanganui River, and north-west of the Raukumara, Te Urewera, and Kaweka Ranges).
Currently occur on five islands within their range: three natural (Aotea/Great Barrier Island, Hauturu/Little Barrier Island, and Waiheke Island), and two translocated (Limestone Island, and Tiritiri Matangi).

Ecology and habitat

The elegant gecko appears to be cathemeral (active both day and night) in nature, although predominantly considered diurnal (day-active), due to its strongly heliothermic nature (being an avid sun basker). As with all members of the Naultinus genus they are primarily arboreal (tree-dwelling), although can at times be found quite low to the ground in prostrate (ground-hugging) vegetation. Although seldom seen on the ground, males can be found travelling between trees in search of mates during the breeding season. As with all green geckos, they possess a strongly prehensile tail which acts as a third-limb/climbing aid when moving through shrubs and trees. They are known to mouth-gape and produce a barking sound as a defensive behaviour against potential predators.

Being an arboreal species, elegant geckos are closely associated with forested habitats, and thus inhabit a wide variety of forest types in the northern North Island, including swamps, scrubland, and mature forest. They appear to favour scrubby/regenerating habitats, but this may be a result of the relative ease of access, and amount of search effort that these sites garner.

Social structure

The elegant gecko is solitary in nature, although can be found at fairly large densities in some habitats. Males show aggressive behaviour toward congeners, especially during the breeding season, and this is easily observable with many males showcasing scarring over their bodies. Mate guarding seems to occur in this species, with males often found in close proximity to females prior to birthing. Although independent at birth, neonates (babies) are often found together and close to the mother for the first few months of life.

Breeding biology

Like all of Aotearoa's gecko species, the elegant gecko is viviparous, giving birth to one or two live young annually, from around Late February through to April. Breeding seems to occur from July through to September, with males performing mate guarding, and following females around. The gestation period is around 7.5 months.
As is the case with many lizard species, mating in green geckos may seem rather violent with the male repeatedly biting the female around the neck and head area. Sexual maturity is reached between 1.5 to 2 years.

Diet

Elegant geckos are omnivores. They are primarily insectivorous in nature but are also known to feed on the nectar, and small fruits of several plant species, and the honeydew of scale insects when they are seasonally available. Being arboreal in nature, their invertebrate prey tends to be predominantly composed of flying insects (moths, flies, beetles), and small spiders. 

Disease

The diseases and parasites of Aotearoa's reptile fauna have been left largely undocumented, and as such, it is hard to give a clear determination of the full spectrum of these for many species.

The elegant gecko, as with many of our other Naultinus species, is a host for at least one species of endoparasitic nematodes in the Skrjabinodon genus (Skrjabinodon poicilandri), as well as at least one strain of Salmonella. Similarly, it is unlikely to be a host for ectoparasitic mites in the wild. Captive collections have been known to host mites, but these have likely shifted onto the animals from different species e.g. MokopirirakauDactylocnemis, and Hoplodactylus geckos.
Wild green geckos have been found with pseudobuphthalmos (build-up of liquid in the spectacle of the eye) and Disecdysis (shedding issues).

Oocysts of Eimeria steidae, as well as two other protozoans, have been recorded in captive animals (Ashby 1971).

Conservation status

Listed in the most recent threat classification as 'At Risk - Declining', due to a mix of land development/clearance of habitat, and predation by mammalian predators.

Interesting notes

The specific name 'elegans' is the Latin form of 'elegant' and references its appearance (a beautifully marked gecko). Th common name mirrors this sentiment.

Genetic studies looking at the Naultinus genus resulted in a phylogenetic and taxonomic review in 2011, with the elegant gecko (N. elegans) and barking gecko (N. punctatus) being elevated from subspecies to full species status.

Māori first described the vocalisations of green geckos to Europeans as being like kata - laughter, being a repetitive call somewhere between a bark and a squeak.

The elegant gecko is the sister species to the Northland green (Naultinus grayii), and Barking gecko (Naultinus punctatus), with the Aupōuri gecko (Naultinus flavirictus) being a more distant relative.

References

Ashby, D.R.H. (1971). Coccidiosis in N. elegans. New Zealand Herpetological Society Newsletter 11, 3.

Fischer, S.M. (2013). Conservation biology and wildlife management in New Zealand: endemic reptile species, urban avifauna, and wetland ecology (unpublished BSc honours dissertation). Massey University: Auckland, New Zealand.

Gill, B.J., & Whitaker, A.H. (1996). New Zealand frogs and reptiles. Auckland: David Bateman Limited.

Gillies, C., & Clout, M. (2003). The prey of domestic cats (Felis catus) in two suburbs of Auckland City, New Zealand. Journal of Zoology259(3), 309-315.

Hardy, G. S. (1972). A review of the parasites of New Zealand reptiles. Tuatara19(3), 165-167.

Hitchmouth, R.A. (1979). The ecology and behaviour of two green gecko (Naultinus) species (Unpublished master’s dissertation). University of Auckland, Auckland, New Zealand.

Hitchmough, R.A., Barr, B., Lettink, M., Monks, J., Reardon, J., Tocher, M., van Winkel, D., Rolfe, J. (2016). Conservation status of New Zealand reptiles, 2015; New Zealand threat classification series 17. Wellington: New Zealand Department of Conservation.

Hitchmough, R., Barr, B., Knox, C., Lettink, M., Monks, J. M., Patterson, G. B., Reardon, J. T., van Winkel, D., Rolfe, J., & Michel, P. (2021). Conservation status of New Zealand reptiles, 2021New Zealand threat classification series 35. Wellington: New Zealand Department of Conversation.

Jewell, T. (2011). A photographic guide to reptiles and amphibians of New Zealand. Auckland: New Holland Publishers Ltd.

McCallum, J., & Harker, F. R. (1982). Reptiles of Little Barrier Island. Tane28, 21-27.

Melzer, S., Hitchmough, R., van Winkel, D., Wedding, C., Chapman, S., & Rixon, M. (2022). Conservation Status of Reptile Species in Tāmaki Makaurau/Auckland. Auckland Council technical report TR2022/3.

Mockett, S. (2017). A review of the parasitic mites of New Zealand skinks and geckos with new host records. New Zealand journal of zoology44(1), 39-48.

Newman, D. G., & Towns, D. R. (1985). A survey of the herpetofauna of the northern and southern blocks, Great Barrier Island, New Zealand. Journal of the Royal Society of New Zealand15(3), 279-287.

Nielson , S.V., Bauer, A.M., Jackman, T.R., Hitchmough, R.A., & Daugherty, C.H. (2011). New Zealand geckos (Diplodactylae): Cryptic diversity in a post-Gondwanan lineage with trans-Tasman affinities. Molecular Phylogenetics and Evolution, 59, 1, 1-22.

Robb, J. (1980). New Zealand amphibians and reptiles in colour. Auckland, New Zealand: Collins.

Robb, J., & Hitchmough, R.A. (1980). Review of the genus Naultinus Gray (Reptilia: Gekknonidae). Records of the Auckland Institute and Museum, 16, 189-200.

Scott, S. N. (2016). Translocation and post-release monitoring techniques of Auckland green gecko (Naultinus elegans elegans) using a penned release: a thesis in partial fulfilment of the requirements for the degree of Master of Science in Conservation Biology, Massey University, Auckland, New Zealand (Doctoral dissertation, Massey University).

van Winkel, D., Baling, M. & Hitchmough, R. (2018). Reptiles and Amphibians of New Zealand: A field guide. Auckland: Auckland University Press, 376 pp.