Knob billed duck (Sarkidiornis melanotos) in flight. From Sub Saharan Africa, Madagascar, and Indochina. : r AIDKE The knob billed duck (Sarkidiornis melanotos) or African comb duck is a type of duck found along the tropical sub tropical wetlands and waterways of Sub Saharan Africa and the island of Madagascar, as Knob billed duck (Sarkidiornis melanotos) female isolated in white backgound in Kruger National park, South Africa Stock Photo Alamy Knob Billed Duck Sarkidiornis Melanotos Stock Image Image of sarkadornis, avian: 164767493 Comb Duck (Sarkidiornis melanotos) flying over a wetland in the South of Ecuador Stock Photo Alamy