I noticed a strange larva in the grub cubicle and quickly realized it was a fat fly larva. Then I saw a fresh, light-colored fly pupa and another maggot of the same apparent type. And then I spotted the dead scarab grub, and another, and another. Three dead and greatly deflated grubs and three large, immature flies. All three flies have now become pupae and have darkened to a deep brown, very much resembling the puparia of the 15-or-so flies that eclosed inside my Osmo*derma emer*icola rearing container. I suspect that these grubs are one of the Osmo*derma species and the fly is the same species that fed on the first batch of Osmo*derma. I'll state my theory again: This fly is a large species and needs a large grub to feed on. I think it must specialize on Osmo*derma.