Lomandra rigida, commonly known as stiff mat rush, is a herbaceous perennial plant endemic to the southern coast of Southwest Australia.

First described by Jacques Labillardière in 1805, using specimens he obtained while voyaging along the Australian coast.

[1] The species was assigned to genus Xerotes by Robert Brown in 1810, this combination is currently regarded as a synonym for the original description.

[3] They are a dioecious species, separated as male and female individuals, that present cream or yellow flowers around October to December.

[4] Endemic to sand on granitic outcrops at the coast of the eastern Esperance Plains and offshore islands at the Recherche Archipelago.