Mokopirirakau nebulosus

Cloudy gecko

Mokopirirakau nebulosus
(McCann, 1955)

Cloudy gecko (Whenua Hou/Codfish Island) © James Reardon
Image attribution
Cloudy gecko (Whenua Hou/Codfish Island). © James Reardon
Herpetofaunal category
NZ Geckos
Species complex
Conservation Status
At Risk - Recovering
Previous scientific names
Hoplodactylus nebulosus
Common names
Cloudy gecko

Length: SVL up to 90mm, with the tail being equal to the body length

Weight: up to 26 grams

Description

An elusive species of forest gecko from Stewart Island and surrounding islands, known for its eccentric cloudy appearance. SVL up to 90 mm. Dorsal surface typically brown, grey, olive-grey, dark green, or pink-brown with large W-shaped chevrons, markings or blotches. These are often discernible as diamonds either side of the mid dorsal region that appear to form pairs, and can be continuous, forming irregular longitudinal stripes. Markings are variable, but are typically pale grey or yellow and are often edged black. Dorsal surface sometimes bears dark speckles. Typical V-shaped marking present on head, as seen in some other Mokopirirakau species. Pale stripe extending from ear opening to eye also present. Lateral surfaces are the same colour as dorsal surface but typically lack the striking dorsal patterns. Instead, they are either uniform or bear irregular pale blotches. Speckles are sometimes present on the lateral surfaces too. Ventral surface uniform grey or cream, with dark speckles or longitudinal stripes. Eye colour olive-grey. Mouth interior yellow to bright orange, tongue is often pinkish with diffuse-grey tip (similar to the closely related Tākitimu gecko, Mokopirirakau cryptozoicus), dark grey, or grey all over with yellow-orange edges. In tact tail equal to or slightly shorter than body length (SVL). Soles of feet grey or cream (van Winkel et al. 2018; Jewell 2008; Thomas 1981)

Life expectancy

Estimates for captive animals of the Mokopirirakau species complex range from 20-30 years (D. Keall, personal communication, September 21, 2016).

Distribution

Known from mainland Stewart Island (few records exist here and it is unknown if the species still exists here), and outlying islands such as Codfish Island/Whenua Hou, and the Tītī/Muttonbird Islands. Cloudy gecko densities on predator-free offshore islands appear to be much higher, perhaps as a consequence of limited or no major predators, or due to habitat features (i.e. Mokopirirakau can be extremely difficult to find in highly complex mature podocarp/hardwood forest)(van Winkel et al. 2018; Jewell 2008).

Ecology and habitat

Cloudy geckos are primarily nocturnal or cathemeral, arboreal and terrestrial. They may bask in the open or in partial concealment. This species inhabits scrub, shrubland, and lowland forest. It may also inhabit rocky areas, such as bluffs, rock tors, and loose rocks scattered across the ground (van Winkel et al. 2018; Jewell 2008). This species has also been known to inhabit buildings and other man-made structures. Remarkably, one population has been recorded from a tiny, barren rock stack that is mostly bare rock with a few shrubs. This rock stack also has a dense colony of seals. On Kundy Island/ Kani, cloudy geckos appear to prefer old Olearia trees that have plenty of cavities, overhanging bark, and plenty of vegetation such as Blechnum ferns around the base. 

Social structure

Many Mokopirirakau species are known for being relatively solitary, however, cloudy geckos have been found in extremely high densities/aggregations on some predator-free offshore islands in artificial habitat (man-made structures).

Breeding biology

Largely unknown. 

Diet

Consumes a variety of invertebrates such as beetles, spiders, and moths. Also most-likely consumes the nectar from flowers and the fruits of native trees.

Disease

Largely unknown.

Conservation

DOC classify the species as 'At risk: recovering' (Hitchmough et al. 2016). Cloudy geckos are not being actively managed and are present in moderate-high numbers on multiple predator-free offshore islands. Accordingly, they are at no immediate risk of extinction. Monitoring and surveys have been conducted to learn more about this species. Future surveys could be targeted at mainland Stewart Island, as cloudy geckos are seldom-seen there. 

Interesting notes

Cloudy geckos are very closely related to the Tākitimu gecko (Mokopirirakau cryptozoicus) (Chapple and Hitchmough 2016; Nielsen et al. 2011).

The holotype specimen was collected in a birds nest approximately 13 feet from the ground (McCann 1955).

References

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

McCann, C., 1955. The lizards of New Zealand. Gekkonidae and Scincidae. Dominion Museum Bulletin 17, 1–127.

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 Evolution, 59(1), 1-22.

Thomas, B.W. (1981). Hoplodactylus rakiurae n.sp. (Reptilia: Gekkonidae) from Stewart Island, New Zealand, and comments on the taxonomic status of Heteropholis nebulosus McCann. New Zealand Journal of Zoology. 8:1, 33-47.

van Winkel, D., Baling, M., Hitchmough, R. 2018. Reptiles and amphibians of New Zealand – a field guide. Auckland university press, Auckland New Zealand.