Just now, I noticed something other than (well, in addition to) the usual fruit fly buzzing around the lamp by my desk. It turned out to be some sort of moth in the family Gracillariidae:
This 7-mm moth has a similar posture to the Caloptilia I saw in October, and it could be a member of that genus, although I’m wondering if it might be Gracillaria syringella, the lilac leafminer, which was a Caloptilia until a few years ago. Like Caloptilia species, it starts out as a leafminer and then exits the mine to make a leaf cone and completes its development in this shelter. It feeds on a number of other plants in addition to lilac. It has been found in Canada and the northeastern US but is probably introduced from Europe.
[Added 8/24/2013: I now believe this is Caloptilia serotinella, which feeds on black cherry.]
Whether or not I’m right about what this moth is, I just thought I’d bring attention to the fact that while some moths live only a few days as adults, others live many months and overwinter in this form. That some of the tiny leaf-mining moths do this first came to my attention last winter while teaching an animal tracking class. I stopped at one point to check out a big chunk of bark that had blown off a tree in the previous night’s storm, and was surprised to find a tiny gracillariid clinging to what had been the sheltered side of the bark. At the end of September, when the moth pictured below (Phyllonorycter apparella) emerged from a quaking aspen leaf I had collected, I asked Terry Harrison if it was normal for these moths to emerge so late in the year and spend the winter behind tree bark. He replied that yes, “many lithocolletine gracillariids such as Phyllonorycter overwinter as adults. In fact, I know a couple of people who do a New Year’s Day excursion to collect overwintering gracillariid adults under bark.” Caloptilia and Gracillaria are gracillariines rather than lithocolletines, but evidently they do it too*. I’m guessing the visitor to my desk lamp had been hibernating in the wood pile and was awoken when it found itself warming by the stove among some logs I had brought in this morning.
* Added a few weeks later: I just came across Clemens’ original (1864) description of Caloptilia coroniella, which was based on one of several adults found under the loose bark of trees in winter.