Elm Zigzag Sawfly Aproceros leucopoda

This sawfly earned its memorable name from the distinctive zigzag damage pattern that larvae create across elm leaves as they feed, leaving a visual signature of their presence. Native to eastern Asia, this species is a shockingly successful invader: first reaching Europe in 2003, then rapidly jumping to North America in 2020. This remarkably swift colonization demonstrates how global trade and modern transportation enable small insects to establish themselves on new continents with startling speed, raising concerns among scientists watching its expanding range.