The frequency of thelytokous parthenogenesis in European-derived Apis mellifera virgin queens

Thelytokous parthenogenesis is the asexual production of female progeny. In the honey bee, Apis mellifera, thelytoky is unknown from mated queens, but can occur in virgin queens that have been induced to lay. We used microsatellite markers to quantify theltyoky in virgin A. mellifera queens of European origin that were sham inseminated with saline and/or narcotised with carbon dioxide. Of 20 queens, 17 (85%) produced at least one daughter thelytokously during an 8-week period. One exceptional queen produced 19% thelytokous progeny, though few total offspring (20 daughters in 107 pupae). The average proportion of thelytokous progeny among the remaining queens was 0.9% (range 0–3.5%), with the balance being males. These results are consistent with observations from the pre-molecular biology era that virgin honey bee queens of non-African subspecies regularly produce thelytokous offspring at low frequency and indicate that there is significant natural variation in the capacity for thelytoky among these queens.