Abstract
A taxonomic synopsis of the orchid genus Pterichis in Ecuador is presented. All national representatives of this genus are characterized and their floral segments are illustrated. Four new species and two new varieties are described. An updated key to Ecuadorian Pterichis is provided. Plants of the genus are growing mostly as terrestrial herbs at the altitude of 2,300-4,110 m. Often two or more species co-occur in the area of 25 × 25 km. Their occurrence was reported from three ecoregions-the Eastern Cordillera real montane forests, the Northern Andean páramo and the Northwestern Andean montane forests. Seven Ecuadorian Pterichis are endemic.