Calothamnus villosus is an evergreen shrub sometimes growing to a height of 2 metres (7 ft).

[2][3][4] The flowers are blood red and arranged in bottlebrush-like clusters about 30 millimetres (1 in) long on one side of the stem that was the new growth of the previous year.

Flowering occurs from March to December and is followed by fruits which are smooth, woody, approximately spherical capsules with two prominently thickened lobes at the top.

[2][3][4] Calothamnus villosus was first formally described in 1812 by Robert Brown in William Aiton's Hortus Kewensis.

[4] It is most common in the Cape Le Grand National Park and in the Mount Burdett Nature Reserve.