Eucalyptus rigens, commonly known as saltlake mallee, is a species of sprawling mallee that is endemic to the southwest of Western Australia. It has smooth bark, lance-shaped adult leaves, flower buds in groups of three on a flattened peduncle and sessile, ribbed fruit.
Eucalyptus rigens is a sprawling, sometimes almost prostrate mallee that typically grows to a height of . It has smooth grey over white bark that peels in strips. Young plants and coppice regrowth have leaves that are up to long and wide. Adult leaves are the same shade of greyish to light green on both sides, lance-shaped, up to long and wide, firm, stiff and often erect. The flower buds are arranged in leaf axils in groups of three on a strongly flattened peduncle up to long. Mature buds are oval, ribbed, up to long and wide with a ribbed, conical operculum. Flowering occurs from July to September and the flowers are creamy white. The fruit is a woody, sessile, cup-shaped or conical capsule long and wide with the valves near rim level.[1] [2]
Eucalyptus rigens was first formally described by the botanists Ian Brooker and Stephen Hopper in 1989 in the journal Nuytsia from material they collected in the Truslove Nature Reserve near Grass Patch.[3] The specific epithet (rigens) is a Latin word meaning "stiff" or "rigid", referring to the leaves.
Saltlake mallee grows in sandy soils around the edges of salt lakes, usually in mallee shrubland, to the north and north-east of Esperance.[2]
This mallee is classified as "not threatened" by the Western Australian Government Department of Parks and Wildlife.