No-host-shift
Guides
Coptodisca juglandiella
Walnut Shield-bearer
Coptodisca juglandiella is a Nearctic leafminer moth in the family Heliozelidae, first described by Chambers in 1874. Native to North America, it was discovered in Hungary in 2019 as a new invasive species for Europe. The larvae feed internally on walnut leaves, creating distinctive blotch mines. Unlike its congener C. lucifluella, it has not undergone a host plant shift since introduction to Europe.