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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. 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 can not 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 6 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.
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