Though my record hasn’t yet been verified, I’m sure these tiny creatures, on the undersides of Alder leaves, are the Pterocallis maculata species of aphid, also known as the Green-barred alder aphid.

It’s the green colour and barred markings that make me fairly certain of my identification, particularly after checking the images and information on the Influential Points website.

According to iRecord, mine is only the third Welsh record, with the other two being found in October 2024, in Merthyr at the head of one the south Wales valleys, and October 2025, in an industrial area north-east of Cardiff Bay. Outside of Wales, this species has been found at just ten locations in England, one in Northern Ireland, and none in Scotland. I can’t help but wonder whether these aphids are really as rare as those records imply or whether it’s simply the case that most people just don’t record aphids.