Abstract
Thalictrum mairei (Ranunculaceae) has been previously placed in synonymy with T. leuconotum based on non-type material of the former name. Critical examination of the type material of T. mairei reveals that it is actually synonymous with T. foliolosum, not T. leuconotum. We therefore reduce T. mairei to the synonymy of T. foliolosum herein. We also clarify morphological distinction among T. leuconotum, T. sinomacrostigma, T. uncatum var. angustialatum and T. uncatum var. uncatum. Lectotypification is proposed for T. falconeri (another synonym of T. foliolosum) and T. foliolosum.