Subspecies
Hybrids with "red bishop", probably Northern Red Bishop (Euplectes franciscanus), reported in captivity. Subspecies eques appears to interbreed with nominate in southern Tanzania, but may be segregated in Burundi and western Tanzania. Proposed subspecies sassii (described from north-western shore of L Tanganyika) synonymized with eques.
The following 3 subspecies are recognised:
eques (Hartlaub, 1863) - Central African Republic, western and southern Sudan, southern and eastern Ethiopia, western Rwanda, western Burundi, southern Uganda and Kenya south to southern Tanzania.
asymmetrurus (Reichenow, 1891) - São Tomé, western Gabon, PRCongo, western DRCongo and Angola.
albonotatus (Cassin, 1848) - Southern Tanzania, south-eastern DRCongo, Zambia, Malawi, north-eastern Namibia (Caprivi region), northern and eastern Botswana, Zimbabwe, southern Mozambique, Swaziland and eastern South Africa.
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Field Guide to the Birds of Australia Simpson, K., and Day, N., 1999, 6th Edition, Viking ISBN 0 670 87918 5
Reader's Digest Complete Book of Australian Birds 1988, 2nd Edition, Reader's Digest ISBN 0 949819 99 9
What Bird is That? 1984, Revised Edition, Angus & Robertson, Sydney ISBN 0 207 14846 5
Handbook of Australian, New Zealand & Antarctic Birds 1990 - , Oxford University Press, Melbourne ISBN 0 19 553244 9
BirdLife International Species Factsheet