Vol. 11 Issue 3, Fall 2006
By Rachelle Hill
Milkweed Beetle
Photo by Liam McGranahan
The Milkweed Beetle (Tetraopes tetrophthalmus) is also known as the Eastern Milkweed Longhorn Beetle and the Red Milkweed Beetle, because of its red color and black spots. It has long, horn-like antennae that are about as long as its body.
As host-specific insects on the milkweed plant, they spend their life cycle on this plant and get both their food and shelter from it. You can find their eggs on the milkweed stems near or just below the soil line.
The beetle’s life cycle follows a seasonal pattern. Larvae make their way in the stems and then winter in the roots. They pupate in the spring, and the adults emerge in early summer then mate and die off by fall. The larvae of the milkweed beetle are poisonous to birds. You can find this insect anywhere where there are milkweed plants.