The superfamily Rhinocerotoidea can be traced back to the early Eocene -- about 50 million years ago -- with early precursors such as Hyrachyus .
Rhinocerotoidea includes modern rhinoceroses .
The superfamily Rhinocerotoidea , which includes modern rhinoceroses , can be traced back to the early Eocene -- about 50 million years ago -- with early precursors such as Hyrachyus .