Allium leaf miner (Phytomyza gymnostoma) is an insect pest of leeks. It is a native of Europe and was first detected in Pennsylvania in 2015.
Leeks are the primary host of this pest, but other plants in the genus Allium can be infested. Larvae mine through the leaves and into the bulb. Entrance and exit holes also provides an entry point for infection.For more information about this plant pest, see the CAPS data sheet and the CABI data sheet.