Leptomerycinae is an extinct subfamily within the ruminant family Leptomerycidae. It contains three genera, Leptomeryx, Pronodens, and Pseudoparablastomeryx, which lived in North America during the Middle Eocene to Middle Miocene. From Wikipedia
The 32-million-year-old species, named Santuccimeryx, offers a unique glimpse into North America's prehistoric biodiversity.
