Some months back I collected some shelf fungi from fallen logs that had a few dozen D. maculata adults on them. I left the samples in an open plastic bag. Since then, beetles have ventured here and there, where I've found them on the floor, usually on their backs, and put them outdoors or in a container. By now I'm sure I've rounded up way more than the original two or three dozen.

A couple days ago I decided to tear into the fungus samples to see if I could find larvae and/or pupae. No pupae were found, but I did find these two larvae, which are now in a container with a few fungus scraps, and have the strong suspicion they will mature into D. maculata. Notice the mite contingent, mainly astride the uppermost larva in the image.