The adult beetle is about 1/4 inch long, with yellowish legs and antennae. The body is yellowish to green with several black spots on the head and thorax and a black colored stripe on the outer margin of each wing cover. The larvae all smaller than the beetle, are dirty-yellow to black, ugly, and spiny. They are 1/2 inch long when full grown. Elm leaf beetle pupae are bright yellow and found at the base of the host tree. The lemon yellow spindle-shaped eggs are laid in clusters on the undersides of the leaves.