The Green Lizard - Lacerta viridis (Eastern) and Lacerta bilineata (formerly L.v.bilineata) (Western).

Introduction

Until recently, these were regarded as a single species divided into separate sub-species. Genetic work suggested that they were, in fact separate species. This was then tested by interbreeding and the results purport to support this. Since, however, they did produce at least some fertile offspring this clashes with my view (and the traditionally accepted view) of the definition of separate species. In addition, I have interbred the two in the past with 100% fertility in both the offspring and their descendants. Accordingly, I will treat them largely as a single species. The animals I keep include both sub-species. The bilineata are descendants from animals obtained from the pet trade and other breeders between 1962 and 1990. The current viridis are descendants of imports from Russia within the last 5 years (although some much earlier viridis blood is perpetuated in the bilineata which may not be totally pure.)

These are a medium sized lacertid typically around 30 cms long although some individuals will reach 400 cms. As adults the vast majority have a base colour, as their name suggests, of green! Most males look much the same, generally being covered with fine black speckles although some can show almost no black at all. The head is sometimes plain green and sometimes the top is speckled with yellow. During the breeding season the males often (but not invariably) display prominent blue cheeks and throats. Occasionally this appears throughout the year albeit to a lesser extent. Females can also range from plain green to green with a range of patterns and markings in black. They are seldom speckled, the marking when present being more likely to be pronounced blotches, sometimes so extensive as to form complex reticulation. Some animals retain two, or even four white lines into adulthood. Some females also have a blue throat and cheeks although this is not as pronounced as in the males. As hatchlings there is little or no green present and two or four pale lines might be present. These lines often become more pronounced as they grow and many animals retain these markings as juveniles whether male or female as they become green. They frequently become far less pronounced as adults - especially in males.

This is a European Protected Species.

Adult male with blue throat and cheeks behind heavily marked adult female with pale blue throat

Accommodation

This species can be kept reasonably well in indoor vivaria (although a hibernation period is essential) but does particularly well in outdoor vivaria although the Eastern form prefers it not to be too damp.
Indoors, a pair could be kept in a vivarium of at least 1m x 0.5m. Although this species is not unduly aggressive, it is large and territorial enough a lizard to make crowding inadvisable.

They will thrive in a semi-desert set up. Hiding places must be provided and ideally the vivarium should contain a substantial heap of sand for burrowing as well. A clean water bowl should be provided but the vivarium should also be lightly sprayed each morning to represent dew as some individuals will only drink this way. They must have good UV lighting and a substantial temperature gradient. The ambient temperature during the summer should be around 25-30ºC during daytime in the summer with a basking hotspot of around 40ºC. At night the temperature should drop to around 15ºC. During the winter, the overall temperature should be held between 5 and 10º.

These animals are superb for outdoor vivaria in most of the UK. In fact, there is a wild colony which has been introduced (illegally) on the south coast and is thriving. There does appear to be a small differential between the Western and Eastern forms as the latter are used to a somewhat drier climate. If dry protected hibernacula are provided this should not prove a problem. A suitable outdoor vivarium can range from a large garden frame upwards. A trio (1 male, 2 females) could be kept in a suitable garden frame. With larger vivaria the ratio should remain around 1 male to 2 females although you will have to be alert for aggression between males. This would seldom result directly in injury but a subordinate male could suffer considerably from stress leading to its premature death. Having said this, I have kept as many as 8 adult males (with a corresponding number of females) in a vivarium with an area of 20 square metres.

The vivarium could be planted with heaths and heathers and even a small ornamental bush or two (I have used both Spanish Gorse and Hebe with considerable success). Grasses and ornamental ground cover plants are also appreciated. It is important, however, that open areas are available for basking and a south facing sand bank will usually be favoured for egg-laying.

These species will generally use hibernacula although some individuals will prefer to dig their own hibernation chamber. For their benefit, a slab of rock firmly supported over a depth of sand will help provide a good hibernating area.

Breeding

Mating takes place during the Spring and is typical of lacertids (see our Breeding pages). After a period of 1 to 2 months the female will be extremely fat - individual egg bulges are often visible. She will usually dig one or two test burrows in a warm spot before choosing where to lay the eggs. She will lay anywhere from 6 to 20 eggs and, ideally, these should be dug up and incubated artificially. When the young hatch, they will usually start feeding within 24 hours of birth.

In optimum conditions, the adults will mate again and produce a second clutch about 6 weeks after the first.

It is wise to keep them separated from the adults for the first few weeks of their lives or they will almost certainly be cannibalised. Growth is extremely rapid and they can go back with the adults within a few weeks - well before they need to hibernate.

Feeding

These are primarily insectivorous lizards and should be fed a suitable range of insects. When fully grown they can handle any of the invertebrates listed in our live foods page. These should be gut loaded and dusted with a suitable multivitamin powder. If you are fortunate enough to have them breed then at this stage they require small insects - third or fourth stage crickets are good as are buffalo worms or other similar sized prey. Gut-loading and vitamin dusting are essential.

Obtaining your animals

In most years, numbers of the Eastern sub-species are imported from the former USSR and can be found in pet shops. A very common with these animals is a disease known as "Tree bark tumour" or, properly, viral papillomata. In its more advanced stages it appears as a growth on the skin rather like its common name. It is almost invariably fatal although animals may live with it for several years. It is also highly infectious. It is spread most commonly by biting and is thus usually evidenced around the back of the body in females and around the head in males. Animals exhibiting any sign of this should be avoided.

It does not appear to be carried down through the eggs to succeeding generations so it might be possible to breed "clean" animals from an infected pair kept in isolation. In such cases, however, the infected animals should never come into contact with any other animals nor should any of their food, decor etc be transferred to other animals. As with any disease you might see with your animals hygiene is essential.

The Western sub-species (and the Eastern sub-species where it occurs in the EU) is one of the "European Protected Species" and are thus relatively rarely available. Nonetheless there are breeders in the UK and the EU who will happily sell some of their offspring. Understandably, most of these breeders do expect you to have the appropriate facilities and knowledge as the objective is to spread breeding colonies among a number of keepers. Naturally, these animals can also be regarded as normally infection and parasite free. Occasionally they might carry a light mite load which, being kept in outdoor vivaria, are dropped from birds. These are not a problem but if their numbers grow excessive this usually indicates that the animals is stressed and/or being kept in in-appropriate conditions. But, always ensure that you get some form of certification that these are captive bred animals.

Similar species include the Balkan or Three-Lined Green Lizards (Lacerta trilineata and Lacerta media) and the Caucasus Green Lizard (Lacerta strigata). Generally speaking these require a little more warmth and are less damp tolerant (or, in the case of the latter MUCH less damp tolerant!).

Next - Timon lepidus - The Eyed Lizard