Type
Age
Age range
18.6–16.3 Ma
Miocene
Burdigalian
Barstovian
Hemingfordian
Arikareean
Barstovian
Hemingfordian
Arikareean
18.718.618.518.418.318.218.118.017.917.817.717.617.517.417.317.217.117.016.916.816.716.616.516.416.316.2