- Pteronetta hartlaubii
Hartlaub's Duck (Pteronetta hartlaubii) is a dark rich chestnut duck of African forests. Formerly included in the paraphyletic "perching duck" assemblage, it was moved to the dabbling ducks later[citation needed]. However, it is fairly distinct from the usual dabbling ducks, being placed in the monotypic genus Pteronetta to reflect this.
Analysis of mtDNA sequences of the cytochrome b and NADH dehydrogenase subunit 2 genes (Johnson & Sorenson, 1999) suggests that it belongs into a very distinct clade - possibly a subfamily of their own - together with the Blue-winged Goose, another African species of waterfowl with uncertain affinities. Remarkably, the upper wing plumage pattern - perhaps the one reliable morphological marker for relationships in the ducks and their close relatives - is not only nearly alike in both species, but unique among all living waterfowl (Madge & Burn, 1987).
Hartlaub's Duck is resident in equatorial West and Central Africa, from Guinea and Sierra Leone east through Nigeria to Sudan, and south to Gabon, Congo and Zaire.