What's the deal with cockroaches and waterbugs?

This has been bugging me for years. Why do some people insist on calling cockroaches waterbugs? My stepbrother and friend have both argued with me (on different occasions) that they’re not cockroaches, but waterbugs. What pushed me over the edge was a few days ago when I saw some insecticide in the grocery store that said it worked on waterbugs. Do the insecticide companies not know what they’re talking about?! I have seen pictures of waterbugs in books and they look little like the creatures in houses. In fact, they look more like stink bugs and chinch bugs that share the order hemiptera. They also swim around in bodies of water, if I’m not mistaken. I believe the insects in the creek near Beckville are waterbugs, though I’m not certain. Nevertheless, houses aren’t bodies of water. So where’s the link? Do cockroaches like water more than your typical insect? They certainly can’t swim very well in it… Anything you could tell me to make the next person who argues with me look stupid would be appreciated.

First off we need to appreciate that as much as it irks taxonomists bug is an English word. As such it can be and has been applied to a whole slew of insects of various orders, or to insects generally, and even sometimes encompasses spiders. So go ahead and call cockroaches bugs if you want to. You will be correct. They are not ‘true’ bugs, and nor are they ‘true’ Scotsmen.

Usually cockroaches aren’t called water bugs. There is one particular species of cockroach, the oriental cockroach, that is properly called a water bug because it likes cool damp places like waterlogged cellars. Most other cockroaches prefer warm conditions and have varying tolerances for dry conditions.

The insecticide companies not only know what they are talking about, they know who they are talking to: the customer. They know that the average customer speaks English and knows SFA entomology. In English a bug is any insect, and a water bug is an oriental cockroach. A ‘true’ water bug is a water scoprion, or a needle bug, or a water boatman or any of a million other terms. But almost never water bug.

You can argue with people about this if you want to. I wouldn’t, since you are no more correct than they are unless you are in an entomology class. Most people speak English, and in English any insect is a bug. Of course you may also be one of those people who insists that meal worms be referred to as Tenebriod larvae and starfish be called sea stars, in which case I wish you much luck in a lifetime dedicated to overturning millennia of usage of the English language.

In my experience, the very large American Cockroach Periplaneta americana is the one that is most often called “waterbug,” while the smaller German and Oriental cockroaches are usually just called cockroaches or roaches. American cockroaches do have a certain superficial similarity to the Giant Waterbug Lethocerus americanus.

American cockroaches generally do have a preference for living in moist areas, and the association with sewers in particular probably has contributed to them popularly being called “waterbugs.”

In my experiences with people who have waterbugs climbing the walls, it’s because they don’t want to admit that I’m staring at a cockroach.