Red-billed quelea far above the bill, and the underparts may have a pink wash. There is much variability within subspecies, and some birds cannot be ascribed to a subspecies based on outward appearance alone. Because of interbreeding, specimens intermediate between subspecies may occur where the ranges of the subspecies overlap, such as at Lake Chad. The female pin-tailed whydah could be mistaken for the red-billed quelea in non-breeding plumage, since both are sparrow-like birds with conical red-coloured bills, but the whydah has a whitish brow between a black stripe through the eye and a black stripe above. Flying flocks make a distinct
Red-billed quelea Three subspecies are recognised. In the field, these are distinguished by differences in male breeding plumage. Formerly, two other subspecies have been described. "Q. quelea spoliator" was described by Phillip Clancey in 1960 on the basis of more greyish nonbreeding plumage of populations of wetter habitats of northeastern South Africa, Swaziland and southern Mozambique. However, further analysis indicated no clear distinction in plumage between it and "Q. quelea lathamii", with no evidence of genetic isolation. Hence it is not recognised as distinct. "Q. quelea intermedia", described by Anton Reichenow in 1886 from east Africa, is regarded a synonym of subspecies