Toropuku stephensi

Southern striped gecko

Toropuku stephensi
(Robb, 1980)

Toropuku stephensi. © Nick Harker
Image attribution
Southern striped geckos. © Nick Harker
Herpetofaunal category
NZ Geckos
Species complex
Conservation Status
Threatened - Nationally Vulnerable
Previous scientific names
Hoplodactylus stephensi
Common names
Southern striped gecko,
Cook Strait/Stephen's Island striped gecko

Length: SVL up to 82mm, with the tail being equal to or longer than the body length

Weight: up to 13.5 grams

Description

Southern striped gecko are a slender bodied, medium-sized gecko reaching a snout to vent length (SVL) of up to 85mm with the tail being ≥ SVL.

The dorsal (upper) surface light to dark tan with wide pale stripes which may be either bright or drab in colouration. Stripes may be clean-edged or indented by mid-dorsal chevron patterning. Stripes converge to a single line along the tail. Lateral surfaces can vary widely from tan-coloured to vibrant tones of red, coral-pink or yellow. Ventral (lower) surface streaked with fine flecks or spots. Brown/grey eyes. A distinctive mouth with a pink lining and tongue; the tongue sometimes has a darker tip. The corners of the mouth are orange, with the orange colouration sometimes extending around the teeth. Rostral scale in close broad contact with nostril. Males have three large pointed scales on each side of the tail base. Toes have extended pads.

Striped gecko can be distinguished from Woodworthia spp. and Dactylocnemis spp. geckos by the presence of orange in the mouth.

Southern striped geckos appear to have proportionally shorter tails and snouts than the northern striped gecko (T. inexpectatus). Southern striped geckos usually have a 'V' pattern between the eyes, compared crescents '()' in northern striped geckos, although abberant individuals with crescent markings have been found in the Queen Charlotte Sound population (Nick Harker personal communication, December 17, 2020).

Life expectancy

A minimum age of 16 years was recorded for one wild individual, with a minimum of 10 years recorded for a captive individual.

Distribution

Takapourewa / Stephens Island and Te Pākeka / Maud Island in the Marlborough Sounds. Translocated from Maud island to another island in the Pelorus Sound during 2019. A third remnant population was discovered in the Queen Charlotte sound during DOC lizard surveys in 2020.

Ecology and habitat

Arboreal and nocturnal. Striped gecko inhabit forest and scrub. On Maud Island the species occurs in a remnant Kokekohe (Dysoxylum spectabile) forest, but is most commonly encountered in patches of NZ flax (Phormium tenax) and bracken fern (Pteridium esculentum) where they can form dense populations of over ~200 per hectare (Nick Harker personal communication, March 3, 2019).

Southern striped geckos are nocturnal. On Maud Island, they are most readily encountered on warm, humid nights either during or just after light precipitation.

Social structure

Striped gecko are elusive, with their social structure and behaviour largely unknown. They are thought to be largely solitary, although can form dense colonies in flax or bracken fern. 

Captive northern striped gecko (T. inexpectatus) do not show the same level of territorial fighting as other species of gecko, with two males able to coexist in the same enclosure with no aggressive behaviour and only one case of behavioural suppression in a juvenile female (D.R.H. Ashby, personal communication, October 11, 2016). Females will sunbathe in close proximity to each other.

Breeding biology

Females are viviparous (live bearing), giving birth to one or two young every second year during late summer/early autumn.

Diet

Largely unknown, however, the diet of most wild New Zealand gecko consists of invertebrates and nectar.

In captivity a close relative - the northern striped gecko (T. inexpectatus) - has been observed actively hunting, although, show more caution and stealth than other native species such as Duvaucel’s gecko (Hoplodactylus duvaucelii) and green geckos (Naultinus spp.) (D.R.H. Ashby, personal communication, September 20, 2016). In captivity northern striped gecko feed on a wide range of winged insects, including lacewings and dobsonfly, as well as fruit.

Disease

The nematode Skrjabinodon poicilandri has been recorded in Toropuku stephensi. Red mites have been observed in captive Northern striped gecko.

Conservation status

DOC classify Toropuku stephensi as 'nationally vulnerable'.

A conservation translocation of southern striped geckos was undertaken in February 2018 whereby 100 striped geckos were caught on Te Pākeka / Maud Island and released onto another island nearby, to establish an additional population of this threatened species.

Interesting notes

Named after Takapourewa - Stephen’s Island, where the species was first discovered.

A second population was discovered by members of the forest and bird protection society on Te Pākeka / Maud Island in 1989.

A third remnant population was discovered in Queen Charlotte Sound during DOC lizard surveys in 2020 (Nick Harker personal communication, January 2020). Given the geographic separation of this population from those in Pelorus Sound, it is possible there may be remnant populations at other sites (on islands or the mainland), which have remained undetected.

References

Gill, B.J., & Whitaker, A.H. (2007).  New Zealand frogs and reptiles. Auckland: David Bateman Limited.

Hare, K.M., & Cree, A. (2005). Natural history of Hoplodactylus stephensi (Reptilia: Gekkonidae) on Stephens Island, Cook Strait, New Zealand. New Zealand Journal of Ecology, 29, 137-142.

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.

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

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

Whitaker, A.H. (1991). Research on the striped gecko (Hoplodactylus stephensi), on Maud Island Pelorus Sound, Marlborough, 6-12 March 1991. Contract Report No. 1094.

Whitaker, T., Hitchmough, R.A., Chappell, R. (1999). A striped gecko (Hoplodactylus stephensi) at Coromandel. Conservation Advisory Science Notes, 232.