My leaf-mining contacts on X/Twitter and now on Bluesky were posting their lovely images of a mine on Poplar leaves that I hadn’t seen before so, of course, I went looking. These photos (and many more) are the result.

Though the UK Moths website information on their distribution states that this moth can be found ‘throughout England, where it is fairly common except in the west’ and that ‘there are records from Scotland and Wales, but very few’, there are, in fact, over a hundred Welsh records and they are scattered throughout the country.

This is Stigmella trimaculella (I love its common name: Three-spot dot), whose larvae munch on the leaves of Populus species – that’s all the various types of Poplar, as well as Aspen. The mine starts out as a thin gallery, widening as the larva grows in size, eventually becoming a silvery blotch. As you can see in the photo below left, the larva is a greenish-yellow in colour and has a brown head. The mines can be found twice each year, between June and July and again from September to October.