Abstract
Blood smears from 43 species of bird, mainly from the South Island of New Zealand, were examined for haematozoon parasites. An undescribed species of Leucocytozoon was discovered in the Fiordland crested penguin, Eudyptes pachyrhynchus. It is assigned the name Leucocytozoon tawaki, and the gametocytes are described. Preliminary observations of its development in Austrosimulium austra‐lense, A. dumbletoni, and A. ungulatum are discussed, and the ookinete, oocyst, and sporozoite stages within these hosts are briefly described.