Sigmodontinae

Sigmodontinae is a subfamily of rodents that includes New World rats and mice. It has many species, and they are found mostly in South America, but also live across much of the New World.

These rodents arrived in South America from Central America near the end of the Miocene, about 5 million years ago, during an event called the Great American Interchange. After arriving, they spread out and adapted to many different places, similar to how Murinae live in the Old World.

The name Sigmodontinae comes from the type genus Sigmodon. This name means "S-tooth" because the molars of these animals have an S-shape when viewed from above. Different groups within Sigmodontinae, like the Wiedomys and Sigmodon genera, have their own special traits and relationships.

Species

Further information: List of sigmodontines

The Sigmodontinae are a group of rodents that includes many kinds of New World rats and mice. There are at least 376 known species. Some scientists think there may be even more.

The Sigmodontinae are divided into several groups called tribes and genera. These groups include many species of rats and mice that live in many different places. Some important groups are:

• Sigmodontalia: This group includes cotton rats and rats that eat fish and crabs, among others.
• Oryzomyalia: This group includes rice rats, marsh rats, and several other rodents.

These rodents live in many parts of South and Central America. They can be found in many different kinds of places, from forests to grasslands.