What were those molecular beach balls?

Brochosomes (Image by Roman Rakitov, INHS)

Pollen would have been an obvious answer, as pollen grains are both common and come in a plethora of forms. But these weren’t pollen grains. They were brochosomes, produced in the malpighian tubules of leafhoppers and serving an as-yet-undetermined function. Perhaps, they have something to do with water retention or protection from predators. Leafhoppers produce these microstructures in such abundance that they often accumulate in the environment, showing up in odd places like the back of a parasitic wasp.

So. 10 points to Joe Wong, who guessed the answer first over on Facebook.

All you ever wanted to learn about Brochosomes, and more:

http://www.inhs.uiuc.edu/~rakitov/brochosomes.html