"That one time and no other the okapi came to the stream"

The okapi is a mammal native to the Ituri rainforest of the African Congo.  It resembles a cross between a zebra and a giraffe (but with a much shorter neck and height).   For centuries, few Westerners had seen the okapi, so it was considered a near-mythic creature to Europeans until 1901, when a carcass was sent to and displayed in London.