September, 2011

Eastern Leaf-footed Bug

True bugs are one of the most confusing groups of insects, due in part, no doubt, to the fact that we use the term "bug" for just about anything that crawls about on more than four legs and/or creeps us out. Another reason is that many people don't know the difference between true bugs and beetles, and the latter usually comes to mind first. Our subject this month is a very good example of a typical true bug, or member of the order Hemiptera. The eastern leaf-footed bug (Leptoglossus phyllopus) is often found in gardens and can even be numerous enough to be a pest. Nymphs cluster in groups and feed together; their bodies are orange and that is a warning color aimed at potential predators.

One of the ways that true bugs differ from many other insects is the form of their mouthparts. Bugs have tube-like mouths, and they can only ingest liquids. In the case of the eastern leaf-footed bug, the liquids are those of plants, sometimes sucked out of the leaves or stems or, very often, out of the fruits. The damage left from their feeding is not as obvious as, say, chewed up leaves or gnawed out fruits. Instead, the removal of juice leaves a discoloration or shriveled area on the plant, sometimes in a circular pattern where the bug had sucked out the liquid from the center.

Leaf-footed bugs (there are several different species) have an interesting way of protecting themselves from predators such as birds. They mimic wasps. When they are simply resting, it is quite a stretch to imagine this resemblance. However, when the insects fly, and they often take flight when frightened, they make a buzzing sound that will make you duck. They also have a reddish color on their back, hidden when their wings are closed. And finally, those large flanges cause their hind legs to droop as they fly, and the general image they present is admirably wasp-like.

If a bug is caught in spite of its disguise, it does have one more defense: stinky liquid is squirted out of small orifices on each side of its body. To humans, the smell is sort of sickly sweet, and some people have even said they LIKE the smell. I think it is rather nasty myself.