Coincya wrightii

Coincya wrightii, known as Lundy cabbage, is a species of primitive brassicoid, endemic to the island of Lundy off the southwestern coast of England, where it is sufficiently isolated to have formed its own species, with its endemic insect pollinators. Coincya wrightii grows natively only on the eastern cliffs and slopes of the island and nowhere else in the world and is a protected species. It reaches up to a metre in height and with its yellow flowers (seen from May to August) it looks a little similar to oil seed rape. Although it is a member of the cabbage family, it tastes unpleasant – it has been described as "triple-distilled essence of Brussels sprout".