I don’t think I’ve ever seem one of these caterpillars before, they are such a strong colour!
Their whole larval lives are spent in the nettle bed – this is why you don’t see them. They are very dark and non-shiny and they have white spots that become more visible as they get bigger.
Southwick Country Park Nature Reserve 
I don’t think I’ve ever seem one of these caterpillars before, they are such a strong colour!
Their whole larval lives are spent in the nettle bed – this is why you don’t see them. They are very dark and non-shiny and they have white spots that become more visible as they get bigger.