Sand lizard, Lacerta agilis
Linnaeus, 1758

History and origin
The Sand lizard was first described by Linnaeus in 1758, the scientific name of this species is Lacerta agilis. Lacerta from latin meaning lizard. Agilis comes from latin and means 'agile' which is not the case for this lizard unlike other Lacerta sp.

Sand lizard - © Daniel Phillips
Female Sand lizard, Lacerta agilis - © Daniel Phillips

Sand lizard - © Stefan Dummermuth
Male Sand lizard, Lacerta agilis - © Stefan Dummermuth

Sand lizard - © Steve LanghamJuvenile Sand lizard, Lacerta agilis - © Steve Langham

Sand lizard - © Stefan Dummermuth
Male Sand lizard, Lacerta agilis - © Stefan Dummermuth

Characteristics
They are characterised by their bulky bodies and their usual darker top of back.

Description
=Size=
They hatch at around 2 to 3 cm long, averaging about 8 cm long growing up to sometimes 10 cm long (measures not including tail, max. adult size tail included is up to 22 cm long).
=Morphology=
They are a short, bulky lizard, they have a large head and tail but lack the equivalent limb size. The limbs are too small for the body build and this means that this lizard is not as it's name suggests 'agilis' - agile in fact they are very slow.
=Patterns & colours=
As juveniles they are usually brown with two light brown lines on the top of the flanks, on the flanks they have light spots bordered by a dark colour. The top of the back has black markings with light spots inside the black marks. Male adults are usually green on the flanks and a brownish back with smaller black markings and lighter scales inside of these black markings, the tail is brown and hind limbs also. Females are more brown, on the flanks they have various dark markings also with a lighter dot or two inside of this dark patch. The coloration and pattern varies with sub-species, in ssp. argus, males have green flanks and uniform brown or orange back, females can be completely uniform brown-orange. For ssp. chersonensis the males can be completely green and be mistaken for Lacerta viridis. For ssp. bosniea the males and females have a thin light line running down the middle of the back. For ssp. exigua they have 3 vivid lines on the top of the flanks and in the middle of the back.

Geographical range
Found throughout central and eastern Europe, found in the Balkans except for most of Greece, the whole of Eastern Europe, Austria, most of Switzerland, all of Germany, Denmark, southern Sweden, in France they are found in the French alps, Jura and Massif central mountains as well as a small area in the eastern Pyrenees where it is also found in Spain. It was introduced into multiple areas in the UK and is found in 3 main populations in southern England and north west England (although native to the Merseyside area).

Subspecies
- agilis - Found in western Germany and west of Tyrol in Austria.
- argus - Found from eastern Germany over much of Central and eastern Europe.
- bosniea - Found in the Balkans.
chersonensis - Found in Romania and western Ukraine.
- exigua -Found from the Dnieper River in central Ukraine eastwards.
- garzoni - Found in the Pyrenees.

Sexual differences
Visible differences are in the patterns, males usually have green flanks where as females are usually brown, for more information please read patterns & colours above.

Seasonal variations
Females are larger in spring due to their eggs.

Diet
They feed mainly on large insects.

Defensive habits
They usually flee at first chance, if caught they don't bite.

Reproduction
Breeding occurs when they wake up from hibernation in spring, a week after, they are all looking for each other and mating begins. After only a few weeks about 10 eggs are laid (extremes are from 4 to 14 eggs) in a moist, warm spot, usually under hey piles, in rotting wood piles and other places of this kind. The eggs incubate for around 10 weeks before hatching.

Sexual maturity, life span
The average life span for Lacerta agilis is about 12 years, they reach their sexual maturity when they are two years old for males and three years for females.

Habits
They are active by day. They can be found in densities of 30 to 100 per hectare in suitable habitat. They are more intelligent then other green lizards as they seem to be able to sense changes around then and adapt according to different situations such as a threat, rain, sound/vibration.

Habitat
Their typical habitat consists of typical Mediterranean scrub land, dry often densely vegetated with small open areas scattered in places. they are found up to 1000 m in altitude except for southern Spain where they live up to 2100 m in altitude, although they are less common here.

Predators
This species is hunted by birds of prey, snakes (Malpolon most common and only for fully grown specimens). One of the most damaging factors to their populations is cars and humans as we are responsible for the destruction of their fragile habitat. They only real natural predator for a fully grown specimen is a fully grown Montpellier snake, who are the only animal who is capable of immobilising an animal of this size.