A rock-sized rare plant that spends its whole life disguised as a stone has just earned a grim new title: critically endangered. According to the International Union for Conservation of Nature (IUCN), the global wildlife conservation authority, Lithops werneri now survives in only one spot on the planet, a patch of Namibia's Erongo Mountains no bigger than 4 square kilometers (1.5 square miles), and fewer than 200 plants are left there.
