*Voted best prehistoric animal toy figure of 2018 by Prehistoric Time Magazine* Though similar in appearance to the woolly mammoth, the American mastodon is not closely related. The mastodons split from the other members of the order Proboscidea around 25 million years ago. The most well-known of these beasts was the American mastodon, which was the last of the group to go extinct about 11,000 years ago. History: Though the genus name "Mastodon" is no longer used in this creature's scientific name, it's still the most frequently used informal common name for these giant elephant-like animals. The currently accepted genus is Mammut. Mastodons (or mammutids) were not as large as most mammoths or even modern-day elephants and were not as widespread. Scientific Name: Mammut americanum Characteristics:Â Like mammoths, the American mastodon features small ears, a trunk like an elephant, and two long curving tusks.