A tortoise is a land reptile with an exoskeleton, which is a hard shell.
In fact, there is a hard shell on the top (called a carapace) and a hard shell underneath (called a plastron).
How can you tell a male tortoise from a female tortoise? One way to tell the difference between a male and a female tortoise is to turn it around and look at the plastron – the underbelly shell.

a female tortoise with a flat, smooth plastron
A female tortoise has a flat, smooth plastron.
A male tortoise has a concave plastron (it curves inward towards the body). The concave plastron looks like is has a hollow section.

a male tortoise with a concave (hollow) plastron

a male tortoise with a concave plastron
A female tortoise has triangular shapes at the end of the plastron.

Female tortoise with triangular shapes on the end of the plastron
A male tortoise has rounded shapes at the end of the plastron.

Male tortoise with round shapes on the end of the plastron
Photographer: Martina Nicolls
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