Wurmbea is a genus of perennial, corm-bearing herbs in the family Colchicaceae (order Liliales), comprising approximately 50 species distributed across Africa and Australasia. The genus was described by the Swedish botanist Carl Peter Thunberg and published in Novae Genera Plantarum (1781).
Plants in this genus are glabrous (hairless) perennials that grow from corms and produce unbranched stems or scapes. Leaves number 1–3 and are basal or cauline, with sheathing bases. The inflorescence is a spike or, in some species, a solitary flower. Flowers may be bisexual, or the plants may be dioecious (separate male and female individuals) or polygamous; in dioecious species, male and female flowers differ in appearance. The perianth consists of 6 tepals arranged in a single whorl, fused at the base, and persistent after flowering. A distinctive feature of the genus is the presence of 1 or 2 sub-basal nectaries on each tepal, which vary in color — purple, pink, greenish, or white — and are useful in species identification. Stamens number 6; the ovary is superior and 3-locular, with many ovules per loculus. Fruits are loculicidal capsules, and seeds are globose and brown.
Of the roughly 50 accepted species, approximately half are native to sub-Saharan Africa and the other half to Australasia, where 19 species occur endemically across all Australian states. The genus belongs to Colchicaceae, a family otherwise notable for including Colchicum (autumn crocus) and Gloriosa (glory lily), and shares with them a characteristic corm-based growth form and alkaloid chemistry.
Etymology
The genus name Wurmbea was established by Carl Peter Thunberg in 1781, published in Novae Genera Plantarum. It is named in honour of Johann Wurmb, an 18th-century Dutch naturalist who served with the Dutch East India Company (VOC) in Batavia and corresponded with Thunberg.
Distribution
Wurmbea is native to Africa and Australasia. In Australia, 19 endemic species are recorded across all states. The African contingent accounts for roughly half the genus's approximately 50 species. No species are native to the Northern Hemisphere.
Ecology
Species of Wurmbea grow from corms and may be dioecious, polygamous, or hermaphroditic, making the genus of interest for the study of plant breeding-system evolution. The sub-basal nectaries on each tepal likely function as pollinator rewards. In Australia, species occur across varied habitats spanning all states.
