Molecular characterization and population structure of Apis mellifera from Madeira and the Azores

Mitochondrial and microsatellite variation were analyzed in honeybee populations from the Madeiran and Azorean archipelagos. The most frequent mitochondrial haplotypes corresponded to the AIII subset of the African evolutionary lineage of A. mellifera. Genetic variability of these island populations was analyzed in relation to Canarian and continental (Morocco, Portugal and southern Spain) honeybee populations. Island and continental populations were genetically differentiated. Microsatellite analyses supports (i) the distinctness of the Macaronesian honeybee populations, and (ii) the close relationship between Macaronesian and NW African populations. Recent introgression events due to apicultural practices were detected, possibly changing the genetic structure of locally adapted populations.