Holarrhena is a genus of flowering plants in the family Apocynaceae (the dogbane family), placed in the order Gentianales. The genus was first described in 1810 and comprises a small number of species — the World Checklist of Selected Plant Families recognised five as of 2013, with a sixth, Holarrhena parishadii, described from the Palakkad Gap of India's Western Ghats in 2024.
Members of Holarrhena are shrubs or small trees typical of the Apocynaceae, bearing simple opposite leaves and clusters of white flowers. The genus is distributed across tropical and southern Africa and through south, east, and southeast Asia. The most widespread species, Holarrhena pubescens, ranges from eastern and southern Africa through the Indian Subcontinent, Indochina, and parts of China. Holarrhena floribunda occupies western and central Africa, while Holarrhena mitis is native to Sri Lanka and Holarrhena congolensis to the Democratic Republic of the Congo.
Several species, particularly H. pubescens, have a long history of use in traditional medicine across their ranges, notably for the treatment of dysentery, giving rise to the common name "conessi bark" or "kurchi."
Distribution
Holarrhena is native to tropical and southern Africa and to south, east, and southeast Asia. Species range from western and central Africa (H. floribunda) and the Democratic Republic of the Congo (H. congolensis) to Sri Lanka (H. mitis), the Indian Subcontinent, Indochina, and parts of China (H. pubescens).
Taxonomy Notes
The genus was first described in 1810 and is placed in the family Apocynaceae, order Gentianales. As of 2013 five species were accepted by the World Checklist of Selected Plant Families; a sixth species, Holarrhena parishadii, was described from the Western Ghats of India in 2024.
