Red-billed quelea the rear flying over the entire group to a fresh feeding zone at the front, creating an image of a rolling cloud. The conservation status of red-billed quelea is least concern according to the IUCN Red List. The red-billed quelea was one of the many birds described originally by Linnaeus in the landmark 1758 10th edition of his "Systema Naturae". Classifying it in the bunting genus "Emberiza", he gave it the binomial name of "Emberiza quelea". He incorrectly mentioned that it originated in India, probably because ships from the East Indies picked up birds when visiting the African coast during
Cardinal quelea on its head. Gustav Hartlaub was the first to described the cardinal quelea, giving it the scientific name "Hyphantica cardinalis" in 1880, based on specimens that were collected by Emin Pasha near Lado in South-Sudan during 1879. In 1951, Hans von Boetticher regarded the cardinal quelea and red-headed quelea sufficiently different from the red-billed quelea to create a new genus "Queleopsis". Its name in Swahili is "kwelea kidari-chekundu". Molecular phylogeny indicates that ancestors of the quelea species might have originated in India and dispersed to Africa. Based on more recent DNA-analysis, the red-headed quelea forms a clade with the cardinal