Special issue: avian malaria.

Avian malaria parasites or haemosporidia are found in bird species worldwide. This special issue focuses on 3 most commonly studied genera: Haemoproteus, Plasmodium and Leucocytozoon. Seven research articles and reviews are provided to illustrate the breadth of knowledge of the diversity of avian malaria parasites in different regional habitats and across bird species, and the use of avian haemosporidian systems to examine host­parasite eco-evolutionary questions.