Atlantic Lizard
Gallotia atlantica (Peters & Doria, 1882)

Family: Lacertidae - Rock & Wall Lizards

Order: Squamata (Sauria) - Lizards

Class: Reptilia

Phylum: Chordata - Vertebrates

Kingdom: Animalia

Red List status: Least Concern

Atlantic lizard (G. a. mahoratae). Fuerteventura, Canary Islands

Snout-vent length: Up to 105 mm

 

Hatchling SVL: 25-35 mm

RANGE

Restricted to the Canary Islands of Lanzarote, Fuerteventura and their associated islets of Lobos, Graciosa, Alegranza, Monte Clara and Roque del Este. A small population on Grand Canaria probably represents a recent introduction.

            Range            Description            Habitat            Behaviour            Biology            Taxonomy            References

DESCRIPTION

A small to moderate-sized lizard with a pointed snout and large, keeled scales across the back, giving the animal a coarse texture. The tail has a slightly spiny appearance. There is a toothed 'fringe' of scales around the front of the tympanum. The underside is whitish, and 8-12 large scales are present ventrally at mid-body. Adult males are characterised by a longitudinal row of green or bluish spots along the flanks, though the intensity and shade is variable; these patches strongly absorb ultraviolet light. Adult lizards are dark brown to black in body colour with black throats. Young animals are a lighter brown, and may possess several longitudinal stripes and spots along the flanks and dorsum. Adults exhibit sexual dimorphism, with males having larger heads relative to their body size. The throat is normally blackish, in contrast to other Canarian lizards.

Similar species: Few other lizards occur within the Atlantic lizard's range, where it is generally the most common species. The Gran Canaria giant lizard (Gallotia stehlini) has been introduced to Fuerteventura and co-occurs with recently established Atlantic lizard populations on Gran Canaria. This species is larger and more robust, with no fringe around the front of the ear opening, and possesses 16-20 belly scales at midbody. Canary Island skinks differ in colouration, lack green or blue spots, and have a smoother, glossier appearance to the body and tail. Geckos are readily distinguished by their vertical pupils, large rounded heads and expanded digits.

 

HABITAT

Terrestrial in most habitats present on the eastern Canary Islands, including malpais (lava fields), arid scrub, sand dunes and coastal areas. It may also be found in cultivated areas and can be very abundant in human-modified habitats. The species may be absent from young lava fields without vegetation.

Elevation: 0-800 m

 

BEHAVIOUR

The Atlantic lizard is commonly active foraging in vegetation; however, animals are also frequently encountered basking on stones or bare ground alongside paths, usually close enough to vegetation or loose soil to retreat/burrow into cover rapidly when disturbed.

Courtship behaviour: Males inflate their throat pouches and approach females with heads downturned and nodding. Courtship behaviour is simple, and males will immediately mate with receptive females.

Diet: Omnivorous. The Atlantic lizard is preferentially insectivorous, and will also feed from carrion such as bird remains discarded by falcons, but adults will eat fruit and flowers where insects are scarce.

 

BIOLOGY

Breeding biology: A female Atlantic lizard may produce up to three clutches a year, with each containing 1-5 eggs which are laid 3-4 weeks after mating. Young lizards hatch within ten weeks.

Lifespan: Up to 15 years; large males often live for 5 years or more.

 

TAXONOMY

Five subspecies of the Atlantic lizard are recognised, distinguished on the basis of size and colouration. Gallotia atlantica mahoratae, the smallest form, found on Fuerteventura, Lobos and is probably identical to the form described from Gran Canaria as G. a. delibesi. The spots along the flanks are smaller in this form than others, and the throat is paler. Sexual size differences are also less pronounced than in the 'typical' Lanzarote form G. a. atlantica, which is also found on several small islets. G. a. laurae is confined to lava fields on Lanzarote and reaches larger sizes than other subspecies (which rarely exceed 75 mm in snout-vent length); the spots on the flanks sometimes merge in this form. The remaining form is G. a. ibagnezi, also confined to Lanzarote and its outlying islets.

 

REFERENCES

 

Gallotia atlantica, The Reptile Database, J. Craig Venter Institute

Arnold, N. and Ovenden, D. (2004) Collins Field Guide: Reptiles and Amphibians of Britain and Europe HarperCollins, London: 288pp

Font, E. and Molina-Borja, M. (2004) Ultraviolet reflectance of color patches in Gallotia galloti lizards from Tenerife, Canary Islands. in: Prez-Mellado, V., Riera, N. and Perera, A. (eds.) The biology of lacertid lizards. Evolutionary and ecological perspectives. Institut Menorqu d'Estudis. Recerca, 8: 201-221

Molina-Borja, M. (2003) Sexual dimorphism of Gallotia atlantica atlantica and Gallotia atlantica mahoratae (Lacertidae) from the Eastern Canary Islands. Journal of Herpetology  37: 769-772

Gallotia atlantica mahoratae. Fuerteventura, Canary Islands.