On 24th January I was in Sainsburyâs at Forestside, Belfast, Co. Down doing the weekly shop. I was well aware that oranges and lemons with leaves in GB supermarkets had been producing mines of the âsnail trailâ leaf mining micromoth Phyllocnistis citrella. I had searched in previous years without success. On a recent trip to Lanzarote I had found fresh mines on a lemon tree in Manriqueâs garden so I was well tuned-in! My eyes were drawn to boxes of âTaste the Differenceâ easy-peel oranges as I could see that the fruit had sprays of leaves attached. I opened the first box and was somewhat amazed to see mines on the first leaves. In fact most boxes had the leaf mines. The mines are only in the leaf epidermis and on close inspection a thin line of black frass is visible. Fresh mines are white in appearance but after being vacated they quickly turn brown.
The oranges had been imported from Spain where this species can occur in pest proportions. Surprisingly there are no previous records of this adventive but having been alerted Ted Rolston and Andy Crory found mined leaves (and fruit) on oranges in a number of other outlets. Christmas is apparently the best time to look so you might find a welcome Xmas present if you look hard enough.
Dave Allen
