Plague (rainbow) skink Lampropholis delicata

Footprints and Tracks

Paws and feet

Plague skinks may be identified via the segments on their toes, which are called ‘lamellae’: – between 11-13 lamellae on the 4^th toes of the front feet and between 21-23 on the 4^th toes of the rear feet. As lizards can be hard to capture, pre-inked tracking cards serve as a good way for wildlife managers to detect and identify lizard species. A good foot impression on the ink provides a way of counting lamellae and, therefore, identifying which species may be present.

Can be confused with:

Native skinks, particularly copper skinks, look very similar to plague skinks and there are few tell-tale signs to distinguish between them (see other clues, body covering). Therefore, the lamellae count of the front and rear 4^th toe can be very helpful. Native skinks have fewer than 9 lamellae on the front 4^th toe and fewer than 21 lamellae on the rear 4^th toe (see pop-up image at right.)

Dens and nests

Unlike most native skinks, which give birth to live young, plague skinks lay eggs (that is, they are oviparous).  Each female may lay 3-7 eggs, several times per year, but commonly between September and April.  Eggs are white, oval shaped and typically less than 10 mm long and 5 mm in diameter.  The shell is smooth, leathery and may have a pinkish-coloured hue beneath the surface.  Within a population of plague skinks, many of the females may lay their eggs in the same place – this is called a ‘communal clutch’.  The largest communal clutch recorded in New Zealand contained almost 3000 eggs. 

Eggs may be found almost anywhere but are commonly found in gardens beneath pot plants, in compost, under sheets of corrugated iron and anywhere that may provide protection for the eggs until they hatch, approximately 40-60 days after being laid.

Can be confused with:

There is one native New Zealand egg-laying skink species, the Suter’s skink, also known as the diving skink or the egg-laying skink. Its eggs are unlikely to be confused with those of the plague skink, as Suter’s skinks are range-restricted to only a few North Island mainland and island locations, and primarily inhabit boulder beaches and rocky platforms within the intertidal splash zones. Therefore, this species is unlikely to be found in places where plague skinks occur.

Vegetation Damage

Fruits and Flowers

In urban gardens plague skinks have been known to feed on small fruits including strawberries and blackberries, although they prefer to feed on a wide variety of invertebrates, acting as both predators and scavengers. We have no information as to what their damage might look like.

Can be confused with:

Similar types of fruit damage could be caused by other species of skink and by invertebrates.

Kill Sign

Insects or snails (invertebrate)

Plague skinks are not fussy eaters and will readily consume a wide variety of insects including moths, small beetles, amphipods, spiders, slaters, crickets and snails.  It is not known what kill sign is left behind.  Often they eat the entire invertebrate.

Can be confused with:

Other species of skink and invertebrates could cause similar damage.

Other Clues

Distribution

There are established populations of plague skinks throughout much of the North Island including in Auckland, Northland, Waikato, Bay of Plenty, Coromandel, Wanganui, Palmerston North and the Manawatu.

Can be confused with:

Body covering

Plague skinks are covered in scales. They have one large scale on the top of their head, directly between the eye sockets, known as a fronto-parietal head scale. It is the most important factor in distinguishing plague skinks from New Zealand native skinks, which have two smaller scales instead. In the plague skink it is a single scale, shaped like a diamond. In all New Zealand native skinks, it is in two parts, which together look a little like an upside-down heart.

Plague skinks (Lampropholis delicata) were originally named the ‘rainbow skink’ in New Zealand due to the rainbow-coloured sheen that the scales of some adults display at certain angles; however, that name is now reserved for an African species of skink.

Can be confused with:

Plague skinks can look similar to some native skinks, especially copper skinks, in colouring, body shape and size. The difference in fronto-parietal head scale is the most reliable distinguishing feature (see above and right) but can be difficult to see clearly on such small animals. The following additional differences between adult copper and plague skinks, though subtle, can be useful.

	Copper skink (Adult)	Plague skink (Adult)
Main body colour	Warm coppery brown or dark chocolate brown, no  rainbow hues	Greyish brown hues, rainbow sheen in some adult individuals
Belly colour and pattern	Yellow to yellow-green, usually speckled (sometimes quite heavily)	Often smooth cream or grey. Throat sometimes speckled but not the belly.
Lip markings	More distinct, noticeable	Less noticeable
Body shape	Less slender	More slender