Eight species of Ischnura are known from Colombia; five of them are Andean endemics, four from the Eastern Cordillera and one from the Central Cordillera. Here, we describe a new species thus far known only from the Central Cordillera, Ischnura solitaria sp. nov. (Holotype ♂ from Belmira, Antioquia, Colombia, 6.711305°N, 75.628503°W, 2 615 m a.s.l.). Despite several searching efforts close to this locality, it has only been found at this wetlands site with few individuals. Due to the low population density of less than 50 individuals and the lack of action to protect the extremely small area where the species occurs, it matches the IUCN requirements to be considered »Critically Endangered«. A taxonomic key to males of Ischnura spp. in Colombia, a discussion on the type locality for the rare I. indivisa and the presence of I. fluviatilis in Colombia are included.