Abstract
Hebe arganthera is described and illustrated. The new species is a shrub with dull green leaves, prominent leaf‐base scars, a narrow sinus in the leaf bud, opposite flowers at least basally, white anthers, and small seeds. It is confined to well‐lit sites on limestone and marble outcrops in Fiordland, southern New Zealand. We compare it with H. cockayneana, H. rupicola, and H. subalpina. It is known from three sites only and is considered to be vulnerable. We provide a key to all the species of Hebe known from Fiordland National Park.