The Golden Beetle, Chrysochus auratus feeds on dogbane which can be found at Fermilab within many of the prairie plots and along some of its paths and roads. As an adult it eats the leaves of the plant and as a laravae it feed on the roots. The golden beetle has also been reported to feed on milkweed. It is one of the most brilliantly colored of the leaf beetles with metallic, blue-green outer wings. Adults appear as early as May, but can be found in greater numbers at Fermilab in July and August. Females lay eggs throughout the summer in groups of two or three, usually on the undersides of dogbane leaves. The eggs are covered in a small cone of excrement to form a capsule. After the larvae hatches from the egg it eats through the capsule and drops to the ground. Here it tunnels to the roots of the dogbane where it feeds. Since larvae at various growth stages can be found on the roots as late as November, it is likely that pupation takes place in the spring.

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