干旱区生态环境知识资源中心

The genus Rorida J.F. Gmel. is resurrected for Cleome L. sect. Thylacophora Franch. within the non-monophyletic Cleome. Rorida is strongly supported as monophyletic by molecular data and is also morphologically very distinctive, with simple leaves, four stamens, and triangular, very shortly clawed, dimorphic petals, appendaged at the base. Twelve species are recognized in desert and semidesert regions from northeastern Africa through the Arabian Peninsula to Afghanistan, Tajikistan, and Pakistan. Rorida cornus-africani is described as new from Somalia and new combinations are made for the other eleven species. All names are typified, including 10 lectotypes designated here. An identification key and distribution maps for all species are provided.