It’s #LeafmineMonday again on social media so here’s another leaf mine to look for when you’re out walking. And this is an easy plant to recognise because I’m sure everyone knows what the Butterfly bush (Buddleja davidii) looks like, right?

These mines on Buddleja leaves, which start as a narrow corridor and quickly develop into a large blotch, are caused by the larvae of a tiny fly, Amauromyza verbasci. The fly also lays its eggs on several other plants, including Mullein and Common figwort.

Mines can be seen from June to November, so it’s almost too late to see these now. The Buddleja plants in my area are already generating new growth but, as you can see from the photo above, the mines may still be seen on the older leaves before they drop.

According to the UK Fly mines website, Amauromyza verbasci is widespread in Britain, though I have to say that I have only seen these mines once, despite a lot of looking at Buddleja bushes. And this sighting was a particularly lucky one for me, as this turned out to be the 1000th species (of flora and fauna) I had recorded on my local biodiversity records centre database.