Lacerta bilineata - Western Green Lizard

Lacerta bilineata
Subsp. bilineata, male: D / Rhineland-Palladium, 11.05.2018 - Note the bluish head.

The Green Lizards are somehow European flagship species - at least in Central Europe with its rather poor Lacertid fauna. These conspicious green, big-sized lizards appear rather "exotic" in the temperate zones of Europe.

 

The Green Lizard has been split into a western and and an eastern taxon: Lacerta bilineata and Lacerta viridis. The Western Green Lizard (Lacerta bilineata) occurs in Italy and Switzerland, France, northern Spain and western Germany, where it is restricted to some areas with viticultural climate in the Rhine River system.

 

At its eastern distribution limit in Northern Italy, Lacerta bilineata has contact zones with Lacerta viridis - and this turned out to be quite problematic: Genetic analysis revealed that the southwestern populations of Lacerta viridis (the so called "Adria Clade") actually are closely related to Lacerta bilineata. And even worse: the two species can hardly be distinguished by external characters. Accordingly, the location of the contact zone of the two species - somewhere in Northern Italy / Slovenia - is still unknown. Maybe, the species split was somehow premature...

Lacerta bilineata lives in warm but not too dry habitats with sufficient hiding places (bushes) and sunny areas.

 

Besides of the nominate subspecies, subspecies chloronota has been recognized for southern Italy and Sicily.

 

In Northern Spain, adults of Lacerta bilineata can be distinguished from Lacerta schreiberi by their green tails. Juveniles of Lacerta schreiberi have characteristic light stripes crossing the flanks which lack in juveniles of Lacerta bilineata.

 

Distinguishing between adults of Lacerta bilineata and Lacerta viridis by external characters may be impossible (see above). Juveniles of Lacerta bilineata often have greenish throats, whereas juveniles of Lacerta viridis show whitish throats.

 

Timon lepidus shows blue ocelli on flanks but no blue heads.

Lacerta bilineata
The distribution ranges of Lacerta bilineata and Lacerta viridis: Note, that the distribution limit of the two species in Northern Italy is poorly known.

Lacerta bilineata
Subsp. bilineata, female: D / Rhineland-Palladium, 11.05.2018 - Note the two light dorsolateral lines which gave this species its name.
Lacerta bilineata
Subsp. bilineata, female with uncommon pattern: D / Rhineland-Palladium, 11.05.2018
Lacerta bilineata
Subsp. bilineata, juvenile: D / near Freiburg, 03.04.2011 - Juveniles frequently show greenish throats
Lacerta bilineata
Subsp. chloronota, male: I/ Cava Grande (Sicily), 01.04.2009
Lacerta bilineata
A slope of the Rhine Valley (Germany): Habitat of Lacerta bilineata and Podarcis muralis.