Woodworthia "Southern Alps"

Southern Alps gecko

Woodworthia "Southern Alps"

Southern Alps gecko (Otago). <a href="https://www.instagram.com/samuelpurdiewildlife/">© Samuel Purdie</a>
Image attribution
Southern Alps gecko (Otago). © Samuel Purdie
Herpetofaunal category
NZ Geckos
Species complex
Conservation Status
At Risk - Declining
Previous scientific names
Hoplodactylus maculatus
Common names
Southern Alps gecko

Length: SVL up to 72mm, with the tail being equal to or slightly longer than the body length

Weight: 5-10 grams

Description

A locally abundant, undescribed taxa from the "Southern Alps gecko" cryptic species complex. Southern Alps geckos are a medium-sized, robust, grey-brown variably marked gecko found throughout the central Eastern South Island high country, from the southern banks of the Rakaia River through to Otago. Most likely encountered basking or under rocks on stable scree slopes and outcrops in the sub-alpine, although known to occur arboreally in shrublands.

Southern Alps Gecko have a greyish top surface with alternating bands/blotches (striping rare). Sides are greyish with pale or darker coloured blotches, flecks or streaks. Belly surface light brown. Mouth lining and tongue pink, commonly with a grey tip on the tongue. Eye colour grey to green. Rostral scale in contact or virtually in contact with nostrils. Toes with tapering distal phalanges. Sub-digital lamellae 9–12.

Separated from the greywacke gecko by the Rakaia River, although vary slightly in morphology:

  • The greywacke gecko is often larger, darker grey/brown in colour, and less stocky, with a longer neck, less finely divided markings and usually lacking the canthal stripe.
  • The Southern Alps gecko varies in body size considerably between individual populations over quite short distances. Neck and snout stocky with a prominent canthal stripe. Silvery grey in colour.

Range abuts:

  • Pygmy gecko (Woodworthia "pygmy") in the Rangitata Valley. Frequently found together under the same rock. Pygmy gecko much smaller, with narrower toes and fewer lamellae (7–9), and rostral scale well separated from nostrils.
  • Waitaha gecko (Woodworthia cf. brunnea) at edges of the Canterbury Plains, but usually separated by altitude, and Waitaha gecko brown (vs. grey), with more contrasting markings, and brown to yellow (vs. green to grey) eye. 
  • Korero gecko (Woodworthia "Otago/Southland large") in the Waitaki Valley and at the northern end of the Dunstan Mountains, but Korero gecko bigger
  • Kawarau gecko (Woodworthia "Cromwell") around Wanaka and at the northern end of the Dunstan Mountains, but Kawarau gecko species slenderer, with longer narrower toes and distinctly longer distal phalanges.

Life expectancy

Unknown, but likely to be similar to other Woodworthia e.g. up to 50+ years.

Distribution

Eastern South Island high country, from the southern bank of the Rakaia River through to northern Otago.

Ecology and habitat

Generally nocturnal but occasionally seen basking in daylight. Primarily terrestrial and saxicolous (rock-dwelling) although some populations are known to be arboreal. Southern Alps geckos live at lower elevations between mountain ranges, but also range up into the alpine (1800 metres a.s.l). Can be found in the stable bases of scree slopes, rocky river terraces and shattered outcrops in dry sub-alpine. Known to inhabit rocks like greywacke and schist. This species has been found to co-occur with the orange-spotted gecko (Mokopirirakau "Roys Peak").

Social structure

Found both solitary and communally, in population groups of up to a dozen or more.

Breeding biology

Twin viviparous offspring born late summer. Likely biennial in high-altitude populations.

Diet

As with other members of the Woodworthia genus, likely to feed on a combination of invertebrates, nectar and seasonal fruit. Potentially a key sub-alpine pollinator and seed spreader. May feed on smaller gecko species including cannibalism.

Disease

Orange mites are typically found on approximately a third of individuals. Ticks are rarely sighted.

Conservation strategy

This species is not being actively managed. Although historically considered to be "Not Threatened" (Hitchmough et al., 2016), its status was elevated to "At Risk: Declining" after the taxon was split into a northern (greywacke gecko) and southern clade (Southern Alps gecko) (Hitchmough et al., 2021). 

Interesting notes

This small gecko gets both its common and TAG names from the large mountain range (known as the Southern Alps) that encompasses the vast majority of its distribution.

Southern Alps geckos are members of the 'common gecko' complex, a group of closely related species which are regionally distributed throughout New Zealand. Historically, most of these were considered a single highly-variable species - Hoplodactylus maculatus (the so called 'common gecko'). The 'common gecko' has now been separated into over ten different species.

The Southern Alps gecko, along with its sister taxa the greywacke gecko sit within the Southern clade of the Woodworthia complex, with the kōrero gecko (Woodworthia "Otago/Southland large") being their closest relative within the group.

References

Frank, H., & Wilson, D. J. (2011). Distribution, status and conservation measures for lizards in limestone areas of South Canterbury, New Zealand. New Zealand Journal of Zoology38(1), 15-28.

Hitchmough R (1997): A Systematic Revision of the New Zealand Gekkonidae. Victoria University, Wellington, 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. (2006). Identifying geckos in Otago. Science & Technical Pub., Department of Conservation.

Jewell, T. (2008). A photographic guide to reptiles and amphibians of New Zealand. Auckland: New Holland.

Jones, C., Moss, K., & Sanders, M. (2005). Diet of hedgehogs (Erinaceus europaeus) in the upper Waitaki Basin, New Zealand: implications for conservation. New Zealand Journal of Ecology, 29-35.

Knox, C. D., Jewell, T. R., & Monks, J. M. (2019). Ecology of orange-spotted geckos (Mokopirirakau “Roys Peak”) in Central Otago and Queenstown-lakes districts. New Zealand Journal of Ecology43(2), 1-9.

Lettink, M., & Monks, J. M. (2019). Ecology of scree skinks (Oligosoma waimatense) in O Tu Wharekai Wetland, mid-Canterbury high country, New Zealand. New Zealand Journal of Ecology43(1).

Nielsen, S. V., Bauer, A. M., Jackman, T. R., Hitchmough, R. A., & Daugherty, C. H. (2011). New Zealand geckos (Diplodactylidae): cryptic diversity in a post-Gondwanan lineage with trans-Tasman affinities. Molecular Phylogenetics and Evolution59(1), 1-22.

O’Donnell, C. F., Weston, K. A., & Monks, J. M. (2017). Impacts of introduced mammalian predators on New Zealand’s alpine fauna. New Zealand Journal of Ecology41(1), 1-22.

van Winkel D, Baling M, Hitchmough R (2019): Reptiles and Amphibians of New Zealand, A Field Guide.  Auckland University Press, Auckland, New Zealand.

Wotton, D. M., Drake, D. R., Powlesland, R. G., & Ladley, J. J. (2016). The role of lizards as seed dispersers in New Zealand. Journal of the Royal Society of New Zealand46(1), 40-65.