 They are widespread across the world and can be found over much of North America and Eurasia from April to June.About 50 species occur in Europe, of which most widely noted is the green longhorn ("Adela reaumurella") which can sometimes reach great abundance; due to climate change its peak flying season is shifting towards spring.In general, they are more plentiful in the Northern Hemisphere, but the family occurs in the Neotropics, sub-Saharan Africa, South-East Asia and Australia too.