Yellow-rumped Tinkerbird (Pogoniulus bilineatus) - HBW 7, p. 184

Taxonomy: Megalæma bilineata Sundevall, 1850, Natal.
Appears to be most closely related to P. subsulphureus and the superspecies formed by P. pusillus and P. chrysoconus; possibly fairly close to P. atroflavus. Yellow-rumped races mfumbiri, leucolaimus and poensis have been thought to represent a separate species, P. leucolaimus, but they intergrade with the three golden-rumped races in E Zaire, Rwanda and Burundi; also, vocal evidence suggests that leucolaimus is conspecific with present species. In view of similarity and intergradation between these two groups, other described forms considered untenable: thus, sharpei (S Ghana), togoensis (Gambia to S Nigeria) and nyansae (W shore L Victoria) regarded as synonymous with leucolaimus; urungenis (S shore L Tanganyika) with mfumbiri; alius (C Kenya) with jacksoni; pallidus (Sokoke Forest) and conciliator (Uluguru Mts) with fischeri; and rovumensis (SE Tanzania), deceptor (E Zimbabwe), riparium (S Mozambique, NE South Africa) and oreonesus (­Malawi) with nominate bilineatus. In addition, single specimen from NW Zambia originally described as separate species, “P. makawai”, on basis of plumage differences and bigger bill, but now generally considered no more than aberrant individual of present species. Six subspecies recognized.