About Chalcides sexlineatus Steindachner, 1891
Chalcides sexlineatus, commonly called the Gran Canaria skink, has a flattened body and a wide head. Its legs are strong, and the northern subspecies has longer legs than the southern subspecies. The southern subspecies has one phrenocular scale, while the northern subspecies usually has two. The average total body length of the species is around 150 mm (6 inches) including the tail, and females are on average a few millimeters longer than males. Individuals from the southern part of the range are slightly smaller than those from the north. In the northeast, the nominate subspecies C. s. sexlineatus has a distinct bright blue tail and a light bluish belly. It has a black dorsolateral band, which is separated from the side by a whitish or yellowish line, and four yellowish brown lines run along its back. In the southwest, the subspecies C. s. bistriatus has a brown tail and a white to yellowish belly. Its back is brown with white spots arranged in a line down the body, and a narrow light band runs along each side of its back. Populations that are intermediate between northern and southern forms have green tails. This species is endemic to the island of Gran Canaria and the small islet Roque de Gando, which are part of the Canary Islands, Spain, and has also been introduced to the island of La Palma. It occupies a wide altitudinal range, from the coast up to 1,850 meters above sea level. Researchers have attributed the distinct morphological differences between the subspecies to volcanic activity on Gran Canaria over the past 2.8 million years. This skink is abundant in nearly all habitats across Gran Canaria, including coastal areas, temperate forests, grasslands, rocky peaks, and agricultural areas. It is rarer in pine forests and the drier areas of southern Gran Canaria. Chalcides sexlineatus is ovoviviparous. Breeding takes place in July and August, and females give birth to between 2 and 7 offspring starting in September. These skinks are elusive and can be difficult to spot. They feed mainly on insect larvae and other small invertebrates.
