The body of the Larger Elm Leaf Beetle differs form most others with its wider, rounded rear, giving it the shape of a traditional light bulb.
Individual Larger Elm Leaf Beetles have a variety of forms. The most recognizable version has a yellow body with four large brown-black spots on the elytra (wing coverings) - two high and two low. As its name suggests, it is often found on elm trees where its larval form devours leaves. Hazel, pecan, and birch trees are also possible host plants. While elm trees have many insect enemies these days, this one is not as troublesome as others like the regular Elm Leaf Beetle. Larger Elm Leaf Beetles are found most often in hardwood forests and woodlands that have elm trees in abundance.
Adults stay in the canopy and females lay fertilized eggs on the bottom of leaves. Newly hatched larvae are a metallic red-brown color and they immediately start chewing the fleshy parts of leaves. Signs of caterpillar presence include the leaf skeletons and a growing brown swath of foliage, almost as though the leaves were scorched. This species rarely eats through a large area of foliage, but occasional outbreaks happen. When ready to pupate, larvae move down the tree into the soil and stay there throughout winter. Adults emerge in the spring. Because only one generation is produced each year, they rarely wreak havoc on a significant scale. When populations are large, however, they are considered a more serious pest. Natural controls like wasp parasites and predators reduce the population the following year, generally preventing occasional outbreaks from becoming widespread.
Scientific Name: Monocesta coryli
Size (Adult; Length): 10mm to 16mm (0.39in to 0.62in)
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Antennae: Beetles have a pair of antennae on the head used as sensors.
Head: The head is home to the insect's eyes, antennae, and mandibles (jaws).
Thorax: Holds the three pairs of legs as well as vital internal organs.
Elytron: One of two wing cases on a Beetle that protects its wings (plural: elytra).
Wings: Appendages used for flying and kept under the elytra until needed.
Abdomen: Houses organs related to circulation, reproduction, and excretion.
Legs: Beetles have three pairs of legs located at the thorax, numbering six legs in all.