Three new Ixora species from Madagascar are described, I. crassipes, I. densithyrsa and I. peculiaris. These species, together with I. siphonantha, are unique within the pantropical genus Ixora because they possess extremely long corolla tubes, up to 23 cm long. In Madagascan Ixoras, corolla tube length shows extreme variation (0.4-23 cm long), perhaps indicating that the radiation process this genus has undergone on the island is, at least partly, pollinator-driven. A determination key and distribution maps are provided for the Madagascan long-tubed species (corolla tubes >15 cm long). Descriptions and illustrations are given for the three new species. © 2007 The Authors.