Three new rare taxa allied to the conspicuous, common four-winged mallee (Eucalyptus tetraptera Turcz.) are described. E. sweedmaniana is a large-leaved and prostrate coastal mallee known only from Mount Arid, Western Australia. E. brandiana, a non-lignotuberous mallet, occupies spongolite hilltops and escarpments near the Fitzgerald River Inlet in Fitzgerald River National Park, Western Australia. A single hybrid mallet, E. arborella × brandiana, is described from the type locality of E. brandiana. Both new species and the new hybrid show potential for horticultural use, given their compact habit, large leaves and conspicuous red floral hypanthia and fruits. E. arborella × brandiana and E. brandiana are particularly at risk, being highly localised endemics that are killed by fire.