True frog facts for kids

Quick facts for kids True frogs
Cyprus water frog (Pelophylax cypriensis)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Amphibia
Order:	Anura
Suborder:	Neobatrachia
Clade:	Ranoidea
Family:	Ranidae Rafinesque, 1814
Synonyms
See text below

True frogs are a large group of frogs known by the scientific name Ranidae. They are found almost everywhere on Earth, living on every continent except Antarctica. You can find them in North America, parts of South America, Europe, Africa (including Madagascar), and Asia. Some even live in New Guinea and northern Australia.

These frogs usually have smooth, moist skin. They are known for their strong, powerful legs and feet with lots of webbing between their toes, which helps them swim. True frogs come in many different sizes, from small ones like the wood frog (Lithobates sylvatica) to much larger species.

Many true frogs love water and live either in it or very close to it. Most species lay their eggs in water, and their young, called tadpoles, grow there before changing into frogs. However, some true frogs live in trees, and a few can even survive in slightly salty water, which is unusual for amphibians!

The Ancient Story of True Frogs

Scientists believe that true frogs and some of their close relatives first appeared in Eurasia (Europe and Asia) and India. They think true frogs are most closely related to a group of frogs found only in India, and that these two groups separated a very long time ago, during a period called the early Eocene epoch.

It was once thought that true frogs came from an ancient supercontinent called Gondwana. The idea was that they evolved on the landmass that became India, and then spread to other parts of the world when India collided with Asia. However, newer studies suggest that true frogs actually started in Eurasia. From there, they spread to India and then to other continents. By the beginning of the Miocene epoch, true frogs had traveled out of Asia and settled on every continent except Antarctica. This is why they are called "cosmopolitan," meaning they are found almost everywhere!

Different Kinds of True Frogs

The world of true frogs is very diverse! Scientists group animals into families, and then into smaller groups called genera (plural of genus). The Ranidae family, or true frogs, has many different genera, each with its own unique species.

Over time, scientists have learned more about these frogs. Some groups that were once considered part of the true frog family have now been reclassified as their own separate families. The genus Rana, which used to include many species, has also been divided into several smaller genera. This helps scientists better understand the relationships between different frog species.

A Look at the Genera

The beautiful Ishikawa's frog (Odorrana ishikawae)

The Bicolored frog (Clinotarsus curtipes), a relative of Meristogenys and Huia

Today, the Ranidae family mainly includes the group called Raninae. Here are some of the genera recognized within the true frog family:

It's important to know that scientists are always learning new things! Sometimes, different groups of scientists have slightly different ways of classifying these frogs, and they are still working to agree on the best way to group them all.

See Also

In Spanish: Ránidos para niños

• Halipegus eccentricus, a tiny worm that sometimes lives inside true frogs in North America.