By PAUL HETZLER

If you announced to your friends that you've seen dust bunnies under your bed come to life, and that you think masked hunters in the house have been attacking you at night, they'd probably all take a step backward -- until you explained that “masked hunters” are a type of assassin bug belonging to the order Hemiptera.

Native to Europe and Africa, masked hunters are now widespread throughout North America. These fierce predators of insects and other arthropods get their name from a curious habit of covering, or masking, themselves with dirt and dust as a means of camouflage. Mature adults are shiny black beetle-like insects measuring about three-quarters of an inch long. During their long “childhood,” though, masked hunters look neither dark nor shiny.

Throughout their several immature (nymph) life stages, their bodies exude a sticky substance, and young masked hunters “glue” fibers from their surroundings onto themselves. (Turns out that it's not just young people that like to play with paste.) In addition, masked hunters have barbed hairs on their legs, which aid in trapping dust. They do a good camo job, and can look for all the world like animated fuzz-blobs.

Masked hunters are seldom found indoors, and then usually in small numbers. There are rare exceptions during sporadic “boom” years when their population spikes, and in such a year more of them may be seen indoors. The good news is that even though they're dusty, masked hunters will “clean house” for you as they prey on pests such as millipedes and bed bugs.

“The good news” is an ominous phrase, indicating bad news will follow. And there are a couple of down sides to having these critters afoot in your home. The first is that masked hunters possess a formidable weapon, a piercing mouthpart called a rostrum. They use this sharp hypodermic needle to impale their prey and inject a toxin to both paralyze it and liquify its insides. Even prey larger than themselves are taken down.

Although they're not aggressive, masked hunters do sometimes bite people when handled, either deliberately or inadvertently. They're most active at night, and although this is rare, they’ve been known to bite people who groggily brushed away a bug that landed on them as they slept. The bite causes painful swelling that can last up to a week. Such an attack may not be discovered until morning, and as the culprit has fled, the injury may be dubbed a spider bite.

The other down side, if you can call it that, is that the corollary to the fact masked hunters really like to eat bed bugs is, if you have lots of “dust bugs” underfoot, you may also have their favorite, and your least favorite, insect as well. If you find a number of masked hunters indoors, check for the presence of bed bugs. But if you see just one or two, chalk it up as a curiosity that seldom causes problems.

One caveat: should you want to discuss an assassin bug called the masked hunter, you probably shouldn't do so around airport security.

Paul Hetzler is a forester and Cornell Cooperative Extension of St. Lawrence County horticulture and natural resources educator.