As MrILoveTheAnts quickly guessed, yesterday’s mystery globules were a fungus garden of agricultural Cyphomyrmex ants. So, 10 points to our winner.
Most fungus-farming ants tend gardens of filamentous hyphae, but some species of the Cyphomyrmex rimosus group eat their fungus as a yeast. These yeasts form the bite-sized pellets visible in the photographs.
Unlike its leaf-cutting cousins, Cyphomyrmex has received little scientific attention. Thus, the implications of yeast farming over hyphal farming remain unknown. Another topic for future research!