The full species status of the North American Northern Harrier Circus (cyaneus) hudsonius – once considered to be a subspecies of Hen Harrier C cyaneus – has received further support in a new DNA analysis of the whole of the genus.
Northern Harrier is actually sister species to the South American Cinereous Harrier C cinereus, and part of a separate lineage to Hen Harrier. African Marsh C ranivorus and Marsh Harriers C aeruginosus also emerged as sister species, while the separate specific status of Réunion C maillardi, Malagasy C macrosceles and Eastern Marsh Harriers C spilonotus has also been upheld.
Oatley, G, Simmons, R E, and Fuchs, J. 2015. A molecular phylogeny of the harriers (Circus, Accipitridae) indicate the role of long distance dispersal and migration in diversification. Molecular Phylogenetics and Evolution: doi:10.1016/j.ympev.2015.01.013.