Ecological and morphological differentiation of the honeybees, Apis mellifera Linnaeus (Hymenoptera: Apidae), of West Africa

Morphometric characters of worker honeybees, Apis mellifera Linnaeus, were analysed by multivariate methods to characterize their populations in the sahelian, dry and wet tropical and equatorial regions of western and eastern Africa (mainly between 0°and 15°N latitude, 18°W and 39°E longitude). Two distinct morphoclusters and a zone of hybridization between them were identified. The bees are identified as Apis mellifera adansonii Latreille and A. m. jemenitica Ruttner. The former subspecies is distributed in the equatorial and wet tropical regions, the latter in the dry tropical and sahelian eco-climatic zones. The hybrid zone extends into the two tropical and savanna biomes and it is suggested that the stability of the hybridization zone is largely the effect of extensive annual fire in the region.