Cheiranthera is a genus of ten species of flowering plants in the family Pittosporaceae (order Apiales), all endemic to Australia. The genus was described by A.Cunn. ex Brongn. and is commonly known as Hand Flowers, Finger Flowers, or Blue Finger Flowers.
Plants are undershrubs with alternate, narrow leaves that have entire or toothed margins. The flowers are pedicellate, borne solitary or in terminal racemes or corymbs, with sepals that are free or cohering at the base and petals that spread from the base without strongly cohering. A distinctive feature is the stamens, which are free and turned to one side of the ovary, with broad-based filaments shorter than the anthers; the anthers are linear-sagittate and open by two apical pores. The ovary is shortly stipitate and two-locular with numerous ovules, topped by a subulate, curved style. The fruit is a hard, two-valved capsule containing numerous seeds.
The genus occurs across all mainland Australian states except the Northern Territory, in eucalypt communities, mallee, and woodland on sandy, well-drained soils in temperate southern Australia. Notable species include Cheiranthera linearis (found in N.S.W., A.C.T., and Vic.), C. telfordii (N.S.W.), C. filifolia and several others from W.A., and C. alternifolia from S.A. (presumed extinct in Victoria).
Distribution
Cheiranthera comprises ten species endemic to Australia, occurring in all mainland states except the Northern Territory — from Queensland and New South Wales through the A.C.T. and Victoria to South Australia and Western Australia. The genus is restricted to temperate southern Australia, inhabiting eucalypt communities, mallee, and woodland on sandy, very well-drained soils.
Ecology
All Cheiranthera species grow in eucalypt communities, mallee, and open woodland on sandy and very well drained soils, primarily in the temperate regions of southern Australia.
Taxonomy Notes
The genus Cheiranthera was described by A.Cunn. ex Brongn. and currently comprises ten accepted species according to the Australian Plant Census (as of April 2020). The NSW Flora Online provides a key distinguishing species by inflorescence type (paniculate vs. corymbose), petal length, leaf apical lobing, and stem/leaf trichome characters. C. telfordii is noted for its paniculate inflorescence and smaller petals (8–10 mm), while C. linearis and C. borealis have corymbose inflorescences with longer petals and differ in leaf lobing and stem surface texture.
Conservation
Cheiranthera alternifolia is listed by the Australian Plant Census as "presumed extinct in Victoria," though it still occurs in South Australia.
