Species of Duma are shrubs, with many flexible branches, whose tips are thornlike. They have white to greyish bark. The leaves are longer than wide, with a very small curved spine at the tip. The flowers are without stalks (petioles). Plants are dioecious. Staminate flowers have eight stamens and a rudimentary or missing pistil; pistillate flowers have staminodes. The fruit is in the form of an ovoid or three-angled achene, which is smooth and shiny.
The genus Duma was created by Tanja Schuster in 2011 for some species previously placed in Muehlenbeckia, but which were shown by molecular phylogenetic studies to form a distinct clade. The name is derived from the Latin for "thorn-bush". Duma is placed in the tribe Polygoneae of the subfamily Polygonoideae. Within the tribe, it is most closely related to the genera Atraphaxis and Polygonum, forming the so-called "DAP clade", and is not so closely related to Muehlenbeckia.
- "Duma T.M.Schust.", Plants of the World Online, Royal Botanic Gardens, Kew, retrieved 2019-03-04
- Schuster, Tanja M.; Reveal, James L.; Bayly, Michael J. & Kron, Kathleen A. (2015), "An updated molecular phylogeny of Polygonoideae (Polygonaceae): Relationships of Oxygonum, Pteroxygonum, and Rumex, and a new circumscription of Koenigia", Taxon, 64 (6): 1188–1208, doi:10.12705/646.5
- Schuster, T.M.; Wilson, K.L. & Kron, K.A. (2011), "Phylogenetic relationships of Muehlenbeckia, Fallopia and Reynoutria (Polygonaceae) investigated with chloroplast and nuclear sequence data", International Journal of Plant Sciences, 172: 1053–1066, doi:10.1086/661293, JSTOR 10.1086/661293