Box Elder Bug – Boisea trivittata

Box Elder Bug – Boisea trivittata
Family Rhopalidae – Scentless Plant Bugs
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Live adult eastern boxelder bugs photographed in the wild at DuPage County, Illinois, USA.

Adult female box elder bugs lay eggs on just about every available surface near their host trees; I've had these bastards lay eggs on t-shirts I'd hung in the sun to dry; those eggs hatched and tiny 1mm nymphs emerged (below). The nymphs are smaller, wingless versions and start out bright red. Boxelder numbers depend greatly on a bountiful crop of maple seed. 2012 was an amazing year for both maples and their dependants (squirrels love helicopters too), with the warmest March on record in the American Midwest.
In the springtime, adult boxelder bugs fly from their overwintering sites and cement clutches of eggs onto any handy surface near the host trees where seeds are available. The eggs hatch in a little over a week, and the nymphs begin their 5-instar march to adulthood. From what I'm seeing at my house here in northern Illinois, there are several waves of overlapping generations; there are always a mix of different instars hiding amidst the maple-seed that fall into lawns or collect in protected places like gutters. All instars eat maple seeds; later instars are carnivorous scavengers of insect carcasses as well. All developmental stages congregate on sunny surfaces, especially wooden surfaces proximate to their food source.

Egg cases and newly hatched nymphs are about 1.5mm

As each succeeding generation matures, it begins the cycle anew as quickly as possible and begin plastering eggs all over the place. This cycle repeats until late autumn when the last adults try to find protected overwintering sites. Like your living room.

Late instar nymph

If you find yourself overrun by these beauties, just mix a little dish soap and water and put it in a spray bottle. You can kill vast quantities of both adults and all instars with a simple spritz (I'm talking outdoors – don't spray this sticky crap on your carpets!) I'm not sure if it kills eggs.

Raking up as many maple seeds as possible and killing as many bugs – adults and nymphs – as possible will help suppress the succeeding year's numbers. Cleaning up leaf or lawn litter in flowerbeds or around foundations can deprive the developing horde of the cover and food they need. 

It also gives the paper wasps a shot at a meal for herself or carryout for her brood (below).

Polistes with meatwad – skinned & chewed box elder bug nymph

Order Hemiptera: True Bugs number almost 5,000 species in North America, and 40,000 worldwide. They have mouthparts formed into a beak, adapted for sucking plant juices or the liquefied insides of their animal prey.
Suborder Auchenorrhyncha – Cicadas & Planthoppers
Suborder Sternorrhyncha – Aphids, scales, mealybugs, jumping plant lice