Oligosoma maccanni

McCann's skink

Oligosoma maccanni
(Patterson & Daugherty, 1990)

McCann's skinks. <a href="https://www.instagram.com/samanimalman/">© Samuel Purdie</a>, <a href="https://www.instagram.com/tim.harker.95/">© Tim Harker</a>.
Image attribution
McCann's skinks. © Samuel Purdie, © Tim Harker.
Herpetofaunal category
NZ Skinks
Species complex
Conservation Status
Not Threatened
Common names
McCann's skink

Length: SVL up to 73mm, with the tail being equal to or slightly longer than the body length

Weight: At least up to 6.34 grams

Description

A beautiful and highly variable small skink with a snout-vent-length (SVL) up to 73 mm.

Dorsal surface typically light brown, grey, or grey-brown, usually with longitudinal stripes, and/or checkerboard-like patterning. Stripes may be smooth, notched, or indistinct. Mid-dorsal stripe typically present but usually broken up on tail. Lateral surfaces typically bear a wide dark brown band that is bordered above and below with pale stripes, which may be notched or smooth. Sometimes there may be pale flecks on the dark lateral band. Ventral surface typically pale white-grey (occasionally yellow) with black speckles on the throat and chin and sometimes on the belly (van Winkel et al. 2018; Jewell 2008). 

Life expectancy

At least up to eight years in the wild (van Winkel et al. 2018)

Distribution

McCann's skinks are very widespread in the eastern South Island, ranging from the main divide from Canterbury to Southland.

Ecology and habitat

McCann's skinks are a diurnal, heliothermic species that can readily be seen sun-basking and hunting. This species typically occupies dry rocky environments from the lowlands up into subalpine regions. They readily inhabit rock tor systems, boulderfields, tallus, scree, rocky herbfield, exotic grasses, herbfield, and tussockland.

Social structure

McCann's skinks are somewhat solitary and don't typically form dense aggregations, however, multiple animals (i.e. more than two) can occasionally be found under suitable retreat sites. 

Breeding biology

Like many other New Zealand lizards, McCann's skinks are considered lecithotrophic and begin vitellogenesis (yolk formation) in spring-autumn. Gestation typically takes 2.5-5 months and occurs between spring and summer (Holmes and Cree 2006). This species breeds annually, with mating occurring in late summer or autumn. Between December and late February 2-6 young are born. Sexual maturity is reach by 2-3 years of age (van Winkel et al. 2018).

Diet

This species will readily eat invertebrates such as spiders, millipedes, beetles, larvae, and flies. It may also eat small fruits and consume nectar from flowers.

Disease

Unknown.

Conservation strategy

This species is not being actively managed and is not at any immediate risk of extinction. However, land development means that this species will often have to be managed circumstantially (e.g. lizard salvages for relocation). 

Interesting notes

McCann's skinks exhibit strong phylogeographic structuring and appear to form seven distinct clades. These clades are thought to have diverged during the Pliocene (O'Neill et al. 2008).

While this species is not considered threatened, habitat modification may impact this species as well as introduced mammalian predators. One study examined 158 hedgehog stomach remains and found that 21% of these contained lizard remains, many of which were McCann's skinks (Spitzen et al. 2009). 

References

Holmes, K. M., & Cree, A. (2006). Annual reproduction in females of a viviparous skink (Oligosoma maccanni) in a subalpine environment. Journal of Herpetology40(2), 141-151.

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

O’Neill, S. B., Chapple, D. G., Daugherty, C. H., & Ritchie, P. A. (2008). Phylogeography of two New Zealand lizards: McCann’s skink (Oligosoma maccanni) and the brown skink (O. zelandicum). Molecular Phylogenetics and Evolution48(3), 1168-1177.

Spitzen–van der Sluijs, A., Spitzen, J., Houston, D., & Stumpel, A. H. (2009). Skink predation by hedgehogs at Macraes Flat, Otago, New Zealand. New Zealand Journal of Ecology, 205-207.

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