Mastodons are mammutid proboscideans in the genus Mammut. Their remains are found in North America and the northernmost parts of South America. These mammals lived from 5.3 million years ago until about 10,000 years ago, during the Zanclean age of the Neogene period until the Meghalayan age of the Quaternary. The following species of mastodons are known:
- M. americanum
- M. cosoensis
- M. matthewi
- M. pacificus
- M. raki
