I’ve been making sporadic progress in sorting through my backlog of photos, and I’m now exactly seven months behind. April 13 saw the conclusion of a story that began with my collecting this scrub oak (Quercus ilicifolia) leaf in early October of 2018:
The brown, wrinkled patch is a leaf mine of a moth in the genus Cameraria (Gracillariidae), but which of the 30 oak-feeding Cameraria species is it? I periodically collect oak Cameraria mines to see if I can figure out ways to distinguish the different species.
I removed this leaf from winter refrigeration on March 1, and on March 10 I discovered this little caterpillar spinning a cocoon in the bottom of the rearing vial:
This was clearly not a Cameraria larva, which would be flattened and legless and would pupate inside the leaf, from which the adult would eventually emerge. It was a larva of one of the bigger micro-moths, probably something in the superfamily Gelechioidea (or maybe a tortricid). It had evidently been inside the mine when I collected the leaf and had spent the winter there.
The next day it was still working on its cocoon; in the photo below it’s lying on its back and adding silk to the ceiling:
On March 20 the larva abandoned its cocoon and disappeared into the crumpled-up piece of toilet paper I had stuffed into the vial for humidity control. At this point I knew my chances of learning the identity of this interloper were not good; a happy, healthy caterpillar does not leave its carefully constructed cocoon behind. On April 13 this ichneumon wasp emerged from a cocoon spun next to the caterpillar’s remains inside the wad of paper.
It turns out I was a bit hasty in saying at the beginning of this post that April 13 was the end of this story. Nearly two months later, on June 10, the adult Cameraria emerged from the same mine:
I tried running it through the key I made here to the known eastern oak-feeding Cameraria species, and I think C. bethunella may be the best match. Unfortunately this is a species complex that needs more work, and I’ve reared much smaller moths with a similar wing pattern from completely different mines. So no name for this moth just yet…