Progress towards resolution of the Indigofera monophylla complex (Fabaceae: Faboideae)

Abstract

The application of the name Indigofera monophylla is clarified by reference to the type held in the Geneva herbarium and a revised description provided. The name has been widely applied to plants with rounded, unifoliolate leaves and some workers have suggested that there are multiple species within this broadly defined group. One of these, with restricted distribution within the Pilbara bioregion, has previously been given the phrase name Indigofera sp. Bungaroo Creek (S. van Leeuwen 4301) and is formally named here as Indigofera rivularis Peter G. Wilson. Two additional species in this complex are also described: Indigofera deserticola Peter G. Wilson & Rowe, is a species of sandplains occurring within the Great Sandy Desert and Dampierland Bioregions, and Indigofera rotula Peter G. Wilson, which is a species with smaller leaves and flowers that occurs primarily in areas south of the Pilbara. A key to these species is provided.