Canadian Herpetological Society





Société d'herpétologie du Canada



Key to the Reptiles of Canada

How to use this key:

A key is a guide to identifying an organism based on the characteristics which distinguish it from related organisms. A key is most useful when you have the animal in hand, but it is sometimes possible to "key out" an animal based on a photograph or detailed description. As you become more familiar with the reptiles of Canada, you will get better at describing the animals you see and it will become easier to use the key.

This key will guide you in identifying a particular animal first as to whether it is a turtle, snake, lizard or some other type of animal. Once this is determined, you will be presented with a series of descriptions guiding you to one particular species. Each question consists of two or more descriptions of particular features of an organism. By selecting the description which most closely matches the animal of interest you will be led either to its identification or to further questions.

Be sure to carefully read each description in its entirety before making a selection. When you have identified the species, selecting that species name will lead you to more information about the natural history of the animal you have keyed out.

What if none of the descriptions match the animal? Do not expect this key to work if you live outside Canada. While it may work in some states adjacent to Canada, the key is designed to distinguish among the species included in this website. If the species you are looking at is not included, the key cannot identify it. It also cannot distinguish it from a similar species which is not included. Similarly it will not work in identifying animals purchased at a pet shop or released pets found in the wild.

If you are reasonably confident that your animal is a native Canadian and still none of the descriptions matches the animal, it is most likely that you have made an error at a previous step and will need to backtrack a bit. Alternatively, since some species are highly variable, you may have an unusual variety. Every attempt has been made to include variants, however, this key is still in an experimental stage and it is possible the we have made the error.

Step 1:

Is it a turtle, lizard, snake or something else?

Turtles
With their characteristic shell, turtles are not easily confused with any other group of organisms found in Canada. The head, four legs and tail of a turtle are covered in scales. The shell may be smooth, or serrated. It is generally hard, but not always. Juveniles of some species are only a few centimeters long, while adult sea turtles can be over a meter long.

Lizards
There are only 7 species of lizards found in Canada as most species are more tropical in nature. Lizards superficially resemble salamanders (which are amphibians), but there are a number of clear differences. Lizards have scales, whereas salamanders have moist, soft skin. In addition, lizards have claws and external ear openings, while salamanders do not.

Snakes
Snakes are the only group of vertebrates in Canada that have no legs. They range in size from only 5-10 cm, for some juveniles, to almost 2 m in length. Many species are highly variable in colour, hence careful examination is required to ensure an accurate identification.


Key to the Amphibians of Canada