Many people have heard of the insect pests known as “water bugs,” but there exists much confusion about which insect species are true water bugs. In many parts of the US, the term water bug is commonly used to refer to several different cockroach pest species, specifically Oriental and American cockroaches, as these two species are often found congregating in moist indoor areas. Many people are in the habit of referring to any large insects they find within damp areas of their home as water bugs, but in these cases, the insect pests in question are usually cockroaches. Experts state that true water bugs belong to a distinct group of insects that are unrelated to cockroaches.

Cockroaches belong to the Blattodea order, while water bugs belong to the Hemiptera order. Insects belonging to the Hemiptera order are commonly referred to as “true bugs,” and very few true bug species are pests of homes and buildings. The true bug pests most commonly encountered within homes include brown marmorated stink bugs and several species of kissing bugs, but these insect pests are not water bugs; instead, pest control professionals and entomologists consider Lethocerus americanus to be the definitive water bug species.

In addition to “water bugs,” Lethocerus americanus specimens are commonly referred to as “toe biters,” as they are known for inflicting very painful bites to people’s toes within shallow bodies of water, such as ponds and creeks. However, water bugs are not inclined to bite humans, and they very rarely appear in homes. Unlike cockroaches, which thrive within homes, water bugs have no interest in establishing shelter indoors, but they may accidentally wander into homes that are located near water bodies. Water bugs may also wind up indoors due to their attraction to artificial lights and high-moisture environments within basements, cellars and crawl spaces.

At around 2 inches in length, the water bug is the largest true bug species in the US, and they are comparable in size to American cockroaches. Unlike reddish-brown cockroaches, water bugs are typically dull grey in color and their antennae are relatively short in length. Water bugs can be found throughout the US, including Massachusetts, and their presence within a home often indicates an indoor plumbing leak or improper drainage system that should be corrected.

Have you ever found water bugs within your home?