Family: Scincidae - Skinks
Order: Squamata - Lizards and Snakes
Phylum: Chordata - Vertebrates
Red List status: Not listed
Endemic to Madagascar, where it is widespread in arid areas of southern Madagascar, as far north as the southern end of the central highlands.
A small skink with four well-developed limbs and a rounded, moderately robust body. The head, forelimbs and frontal portion of the body are black, strikingly contrasting with copper colouration along the rest of the body, the hindlimbs and tail. Nine rows of large white (occasionally yellow) spots extend down the top and sides of the head and along the anterior portion of the body. These may extend slightly past the black portion of the body. Additional white spots and lines occur on the head and forelimbs. The underside is greyish white to bluish; the underside of the hindlimbs and tail is coppery. No longitudinal lines are present.
Similar species: The boulder mabuya is readily distinguished from most Malagasy lizards by its distinctive colour pattern, as well as in details of scalation. T. aureopunctata also exhibits a dark head with pale spots, and T. vato was traditionally assigned to this species. However, T. aureopunctata has a greyish rather than a coppery rear body and a dark brown (not black) head and neck, making the change in colouration appear less pronounced. This species also has traces of tan and brown bordering the white spots, which are absent in T. vato, and fewer than nine rows of spots. These two species also differ in microhabitat preference, with T. aureopunctata often occurring in forest floor habitat, although both may occur in the same area. T. vezo has rows of spots along the entirety of the dorsal surface, never has nine rows of spots on the head, and differs in colouration.
Although moderately widespread, within individual sites the boulder mabuya's distribution is highly localised in areas with boulders, cliffs or other rocky surfaces, from ground level up to about 5 m high on cliff faces. Populations commonly occur in rocky areas bordering watercourses, such as gorges cut by rivers, and may be entirely absent from surrounding areas. They may occur in rocky road cuttings or adjacent to agricultural land, indicating a degree of tolerance to modification of the surrounding habitat where suitable microhabitats are preserved. In some areas, T. vato may completely exclude other ground-dwelling skinks from its preferred microhabitat.
Altitude: Near sea level to at least 220 m
Activity period: Animals are active through much of the day, having been recorded from 9:30 to 17:00.
Breeding biology: This appears to be an oviparous species, with well-developed eggs having been found in the oviducts of animals collected in December. Copulation apparently takes place prior to October. However, no eggs or hatchlings have been identified in the wild for this species.
Species of Trachylepis were previously included in the large tropical skink genus Mabuya, and subsequently within the genus Euprepis.
D'Cruze, N., Olsonn, A., Henson, D., Kumar, S. and Emmett, D. (2009) The amphibians and reptiles of the lower Onilahy river valley, a temporary protected area in southwest Madagascar. Herpetological Conservation and Biology 4: 62-79
Glaw, F. and Vences, M. (2007) A Field Guide to the Amphibians and Reptiles of Madagascar. Third Edition. Cologne, Vences & Glaw Verlag: 496pp
Nussbaum, R.A. and Raxworthy, C.J. (1994) A new species of Mabuya Fitzinger (Reptilia: Squamata: Scincidae) from southern Madagascar Herpetologica 50: 309-319