Eye-plant

Eye-plants were plants native to the planet Spiridon.

The bud that projected from the side of this plant was capable of detecting motion and would slide from side to side to keep an object in view. It was the only know species on Spiridon known to be able to detect the otherwise invisible Spiridons, which made it invaluable as an early warning to their approach. (DW: Planet of the Daleks)