Hemianax ephippiger, the vagrant emperor, is a species of dragonfly in the family Aeshnidae. It is found in Algeria, Angola, Botswana, Cameroon, Chad, the Democratic Republic of the Congo, Ivory Coast, Egypt, Equatorial Guinea, Ethiopia, Gambia, Ghana, Kenya, Madagascar, Malawi, Mauritania, Mauritius, Morocco, Mozambique, Namibia, Niger, Nigeria, São Tomé and Príncipe, Senegal, Seychelles, Somalia, South Africa, Sri Lanka, Sudan, Tanzania, Togo, Uganda, Zambia, Zimbabwe, and possibly Burundi. Recorded in Malta in 1957, and every few years since, it is seen through migration in large numbers. It has never been recorded breeding in the Maltese archipelago.