Ptilotus axillaris, commonly known as mat mulla mulla,[2] is a species of flowering plant in the family Amaranthaceae and is endemic to the north of Western Australia.

It is a prostrate annual herb with several stems, egg-shaped leaves, and pink or magenta, oval or cylindrical spikes of hairy, densely arranged flowers with two fertile stamens.

[2] This species was first described in 1870 by George Bentham from an unpublished description by Ferdinand von Mueller, and was given the name Trichinium axillare in Flora Australiensis.

[3][4] In 1881, von Mueller transferred the species to the genus, Ptilotus as P.

[2] Ptilotus axillaris is listed as "not threatened" by the Government of Western Australia Department of Biodiversity, Conservation and Attractions.