My experiment is about to produce a capped queen cell - this is what happened so far.

In a routine inspection of a new colony, I discovered the queen had stopped laying. The colony was broodless except for a spattering of emerging drones. I pinched the queen and inspected the colony verifying that there wasn't a single egg or larva in the colony.  Next, I placed a donor frame in the colony that had all stages of brood and plenty of eggs. Opposite that frame, I put in a frame from storage that had two queen cups about mid-frame.  I inspected the cups twice every day, and on the second day, an egg appeared in one of the cups. It was policed out only to be followed by another egg on the third day which was also policed out later on the same day. Early on the fourth day a third egg appeared in the same cup, and it was accepted and now about to be capped. 

One possibility is that the workers moved one of the diploid eggs I provided. Another is that they're raising a drone in a queen cell from a haploid egg that a worker laid. Lastly, a worker laid a diploid egg, and they’re producing a queen via thelytokous parthenogenesis. Given the rarity of this trait, and the fact that it would have had to occur on-demand makes it the most unlikely possibility but one that can’t be totally eliminated.  

Next step is to let it mature and see if it's a viable queen.  If it turns out to be a viable queen, I'd say it was likely a moved egg. 
The first photo is the cell with the egg that was accepted and the second photo is the larva. 

https://pix.sfly.com/Ea19WW

https://pix.sfly.com/krbHWh

Bill Hesbach
1133 Coleman Road
Cheshire CT 

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