Plants without borders: new records of two presumed Thai endemic Gesneriaceae in Laos

Botanical expeditions in Laos through a collaboration between Thailand (Queen Sirikit Botanic Garden) and Laos (Pha Tad Ke Botanic Garden) to document plant diversity and collect plants for ex situ conservation, led to the discovery of two species of Gesneriaceae previously believed to be endemic to Thailand: Damrongia trisepala (Barnett) D.J.Middleton & A.Weber and Didymocarpus formosus Nangngam & D.J.Middleton. Information on these species is provided.