The McCann's skink (Oligosoma maccanni) is a species of skink native to New Zealand.
Identification
Oligosoma maccanni can be identified due to their physical features these include but are not limited to an oval shaped body (in cross section), a pointed head, a long tail which tapers downwards, and comparatively long limbs and toes.
McCann's skinks have shiny scales on their skin, they also have two pale and key dorsolateral lines. The O. maccanni 's dorsal stripe does not extend to the end of the tail. The only presence of speckling on the body is under the chin, the O. maccanni 's also have a well-defined pale dorsolateral strip.
McCann's skink have a slim and beautiful figure. In particular, the width of its neck is almost the same as that of the head. It has creamy-grey, yellow or brown soles of the feet and belly. The throat often has fine black speckling. It was discovered by Patterson and Daugherty (1995) that this species had a transparent palpebral disc which was composed of small and rectangular granules which cover its lower eyelid. The background colour of McCann's skink's body is grey-brown with smooth patterns of brown strips. Some of them have grey spots spread along the strips which make a herringbone pattern.
Additionally, there is a morphological variation in McCann's skinks. It was found that McCann's skinks have stripes in Canterbury, but have speckles in Otago. There is also a piece of evidence about the dorsal patterning as it may decrease the risk of being caught by avian predators because most of them mainly rely on vision to prey.
Geographic distribution and habitat
Natural global range
Oligosoma maccanni are endemic to New Zealand which means they only exist in one geographic region.
New Zealand range
Within New Zealand Oligosoma maccanni are located in the South Island. Predominantly in the south eastern section of the island. These being in the regions of Marlborough, Canterbury, Otago, and Southland. It was also reported by Patterson and Daugherty (1990) that McCann's skinks were widespread in Canterbury and Otago where significant land use change, habitat destruction and fragmentation have. Besides, they are spread mostly inland but also live coastal Otago and Bank Peninsula areas.
Habitat
Oligosoma maccanni prefer habitat which is coastal, and or consists of rocky ground as the McCann's skink finds refuge in small cracks between rocks. The McCann's skink hides itself and its young in between and under rocks for protection from predators, and to achieve solar gain by absorbing heat through the rocks during the day time. However, if there are few rocks available, McCann's skinks would shelter inside vegetation with low soil development like herbs and shrubs. For example, they choose to shelter inside Aciphylla spp., as there are long spiny leaves which could provide the perfect protection to O. maccanni . Besides, some skinks in coastal Canterbury areas prefer staying and using marram grass because they could make the habitat in Kaikorete spit get connected with dune vegetation, like Pingao.
Oligosoma maccanni have a preference to open habitat areas, these include areas of native and introduced grass and shrubland including divaricating shrubs such as Discaria toumatoua, Coprosma propinqua, and Muehlenbeckia astonii. Thus, their broad habitat preferences are likely to reduce the vulnerable rates of their population.
Life cycle/ phenology
Mating and breeding stage
McCann's skinks are viviparous and this reproductive process is understood to be an adaptation of Lizards that are endemic to cool climatic regions of the world like New Zealand. New Zealand lizards are typically known to have a long duration of life, with delayed process to reach maturity and a low rate of reproductive success. In particular, the development of embryos have a slow-growth stage during the first three months when compared with later stages during the reproductive process. Additionally, females are annual spring-summer breeders with a 4–5 months' incubation period. During the period of pregnancy, their clutch size may decrease due to a lack of fertilization. It was reported that during the mating period of vitellogenesis which means McCann's skinks mate in autumn season and discharge ovules in spring, male McCann's skinks’ sperms must be stored inside female's reproductive tract for several months to have reproductive success.