The monotypic group Black-necked Weaver (Olive-backed) Ploceus nigricollis brachypterus is recognized as a separate species, Olive-naped Weaver Ploceus brachypterus. The plumage and iris color of Olive-backed Weaver are strikingly different from those of Black-necked Weaver (del Hoyo and Collar 2016). The two apparently hybridize where their ranges abut, a contact zone that has not been studied in detail, but any hybrid zone appears to be quite narrow in comparison to the widespread distributions of each of the two species.