Here are two paper, you might be interested in:

http://link.springer.com/article/10.1007%2Fs00709-014-0645-9

http://link.springer.com/article/10.1007%2Fs00360-008-0288-2

Is their any differences between the aquaporins in honeybees and other solitary bee species? Most of solitary bees preparing a pollen balls for the progeny in some species like Osmia dry and other species not like Anthophora. Very interesting questions, I hope to get more information. 

Direct characterization is not available, but recent publication was from the crop. However, the evaluation of this report seems to be speculative. I think that you can survey the predicted AQP gene from the bee data base.