A Bubotuber is a type of magical plant, the visible part of which is said to resemble a large, thick, black slug. This portion of the plant also squirms of its own volition. The surface of a bubotuber is covered in shiny protrusions, which when squeezed yield a thick, yellowish-green pus that has an odour akin to that of gasoline/petrol. It is unknown where the plant originates from, but is kept at the Hogwarts Greenhouses.