Testudines

Definition

Testudines, also known as turtles and tortoises, are an order of reptiles characterized by a bony or cartilaginous shell developed from their ribs. They are one of the oldest reptile groups, having existed for over 200 million years.

5 Must Know Facts For Your Next Test

1. Turtles and tortoises belong to the order Testudines.
2. Testudines have a unique shell composed of a carapace (top) and plastron (bottom) which is fused to their ribs and spine.
3. Members of Testudines can be found in various habitats including aquatic, semi-aquatic, and terrestrial environments.
4. Testudines exhibit oviparous reproduction, laying eggs on land even if they live in water.
5. The metabolic rate of Testudines is generally slow, contributing to their long lifespan.

Review Questions

• What are the primary structural components of a Testudine's shell?
• In what types of environments can Testudines be found?
• How do Testudines reproduce?

Related terms

Carapace: The dorsal (top) part of the shell in turtles and tortoises.

Plastron: The ventral (bottom) part of the shell in turtles and tortoises.

Oviparous: A mode of reproduction where animals lay eggs that hatch outside the mother's body.