Amphibians

Phylum: Chordata

Class: Amphibia

Common Name: "living both in water and on land"

Distinguishing Features: 

- ectothermic- obtains heat from outside the body or cold blooded. 

- tetrapods- "four-footed

- uses skin to breathe by diffusion 

- has gills then goes through metamorphosis and obtains lungs

Example:

(in comparison to a U.S dime)

Paedophryne amauensis- the world's smallest frog.

Video: http://www.youtube.com/watch?v=GasE3eb58l0