These beautifully colored spurge hawkmoth caterpillars were reported within a few days of each other (look for an adult in the following submission). They all sport a “horn,” but they look different depending on what stage they are in. Young larvae are variously patterned with green, yellow, and black; older larvae have a distinctive red, black, and yellow pattern with a double row of white spots on each side and white speckles. In any stage, they are a welcome sight in the battle against weeds. They are a non-native species that’s been released in the fight against leafy spurge. They can be found in several western states (MT, ID, and OR) as well as eastward to at least Michigan. Their range continues to grow. There can be one to two generations a year.
Photo by Michael Wharton on 7/20/20 near Whitehall, MT.