Calothamnus quadrifidus, commonly known as one-sided bottlebrush, is a plant in the myrtle family, Myrtaceae and is endemic to the south-west of Western Australia. The common name alludes to the arrangement of the flowers in the inflorescence which line up on one side of the stem. It is a shrub with grey-green, pine-like foliage covered with soft hairs and red, four-part flowers in spring. Widely cultivated because of its attractive foliage, colourful, unusual and prolific flowers, it grows in a variety of habitats and soils. In 2010, Alex George published a review of the species based on recent research and described a number of new subspecies.
Calothamnus graniticus, commonly known as granite claw flower, is a plant in the myrtle family, Myrtaceae and is endemic to the south-west of Western Australia. There are two subspecies, both of which have been classified as "near threatened". It is an erect, rounded shrub with pine-like, dark, grey-green foliage and usually bright red flowers. Calothamnus graniticus subsp. graniticus occurs in the Leeuwin-Naturaliste National Park and is the floral emblem of the nearby city of Busselton.
Calothamnus villosus, commonly known as woolly net-bush or silky net-bush, is a plant in the myrtle family, Myrtaceae and is endemic to the south-west of Western Australia. It is a tall shrub, often forming thickets. It has thin, cylindrical leaves and blood red flowers for many months of the year. It is superficially similar to Calothamnus quadrifidus but can be distinguished from that species by its flowers which have five stamen claws compared to the four of C. quadrifidus.
Calothamnus borealis is a plant in the myrtle family, Myrtaceae and is endemic to the south-west of Western Australia. It is a small, erect shrub with crowded, cylindrical leaves and red flowers. It grows in sand surrounded by spinifex or heath. In 2014 Craven, Edwards and Cowley proposed that the species be renamed Melaleuca aquilonia.
Calothamnus arcuatus is a plant in the myrtle family, Myrtaceae and is endemic to the south-west of Western Australia. It is a shrub with prickly, cylindrical leaves with a slight, upward curve and bright red flowers in small groups near the older leaves.
Calothamnus formosus is a plant in the myrtle family, Myrtaceae and is endemic to the south-west of Western Australia. It is a large, spreading, densely foliaged shrub with almost cylindrical, pointed leaves and red flowers in spring or summer. There are two subspecies, differing mainly in the length of their leaves.
Calothamnus macrocarpus is a plant in the myrtle family, Myrtaceae and is endemic to the south-west of Western Australia. It is an erect shrub with bright red flowers in spring and large, almost spherical fruit. It has a limited distribution near Hopetoun.
Calothamnus montanus is a plant in the myrtle family, Myrtaceae and is endemic to the south-west of Western Australia. It is an erect shrub with short, needle-shaped leaves and red flowers with four stamen bundles.
Calothamnus quadrifidus subsp. angustifolia is a plant in the myrtle family, Myrtaceae and is endemic to the south-west of Western Australia. It is similar to other subspecies of Calothamnus quadrifidus except that it has longer leaves than most although in some areas there are plants that are intermediate with Calothamnus quadrifolius subsp. obtusus. The leaves are flat, narrow and prickly.
Calothamnus quadrifidus subsp. asper is a plant in the myrtle family, Myrtaceae and is endemic to the south-west of Western Australia. It is similar to other subspecies of Calothamnus quadrifidus except that its leaves are short, flat and obviously rough and scaly when mature.
Calothamnus quadrifidus subsp. homalophyllus is a plant in the myrtle family, Myrtaceae and is endemic to the south-west of Western Australia. It is similar to other subspecies of Calothamnus quadrifidus except that its leaves are longer and wider.
Calothamnus quadrifidus subsp. obtusus is a plant in the myrtle family, Myrtaceae and is endemic to the south-west of Western Australia. It is similar to other subspecies of Calothamnus quadrifidus except that its leaves are linear and somewhat rough and scaly and the stamen bundles are relatively short.
Calothamnus quadrifidus subsp. petraeus is a plant in the myrtle family, Myrtaceae and is endemic to the south-west of Western Australia. It is similar to other subspecies of Calothamnus quadrifidus except that its leaves are linear and somewhat rough and scaly and the stamen bundles are relatively long.
Calothamnus quadrifidus subsp. quadrifidus is a plant in the myrtle family, Myrtaceae and is endemic to the south-west of Western Australia. It is similar to other subspecies of Calothamnus quadrifidus except that its leaves are circular in cross section and the leaves and flower cup usually have a sparse covering of long, soft hairs.
Calothamnus quadrifidus subsp. seminudus is a plant in the myrtle family, Myrtaceae and is endemic to the south-west of Western Australia. It is similar to other subspecies of Calothamnus quadrifidus except that its leaves are linear and somewhat rough and scaly and the stamen bundles are relatively long.
Calothamnus roseus is a plant in the myrtle family, Myrtaceae and is endemic to the south-west of Western Australia. It is a shrub with needle-shaped, prickly leaves and pink flowers with four stamen bundles.
Calothamnus scabridus is a plant in the myrtle family, Myrtaceae and is endemic to the south-west of Western Australia. It is a shrub with needle-shaped, prickly leaves and red flowers with four stamen bundles.
Calothamnus tuberosus is a plant in the myrtle family, Myrtaceae and is endemic to the south-west of Western Australia. It is a stiff, prickly plant with cylindrical leaves and red flowers, growing near or often on granite boulders. It has a lignotuber and tuberous roots.
Calothamnus validus, commonly known as Barrens clawflower, is a plant in the myrtle family, Myrtaceae and is endemic to the south-west of Western Australia. It is an upright or rounded shrub with stiff, cylindrical but not sharply pointed leaves and red, 4-part flowers. The common name derives from the location, West Mount Barren, where it was found by Spencer Moore, the author of its formal description. It is commonly cultivated and has sometimes escaped from gardens in Western Australia.
Eremaea violacea is a plant in the myrtle family, Myrtaceae and is endemic to the south-west of Western Australia. It is low, spreading shrub with narrow, prickly leaves and which bears violet-coloured flowers on short side branches.
