Turkish autumn-flowering species of Colchicum (Colchicaceae) with large, broad hysteranthous leaves are taxonomically and morphologically revised, with comments on conditions in other areas covered by the distributions. Three new species are described (C. paschei, C. dolichantherum, C. imperatoris-friderici), all endemic to Turkey. Synonym lists, typifications, chromosome numbers, and notes on phenology, vegetative reproduction, phytogeography and ecology are provided for the whole group, and relationships to other species are discussed.
