Two more "Praeovibos"-like genera were named in America in the 19th century, "Bootherium" and "Symbos", which are now identified as the male and female forms of a single, sexually dimorphic species, the "woodland muskox", "Bootherium bombifrons". "Bootherium" inhabited open woodland areas of North America during the late Pleistocene, from Alaska to Texas and maybe even Mexico, but was most common in the Southern United States, while "Ovibos" replaced it in the tundra-steppe to the north, immediately south of the Laurentian ice sheet.