Types of True Bugs: 10 Common Species
Piercing, straw-like beaks and wings that overlap in an X on the back. This guide covers the 10 true bugs people find most often.
Quick list
How to narrow it down
Narrow it down with three quick checks. Count the legs: insects have six, spiders and ticks have eight, and centipedes and millipedes have many more. Check for wings, even folded ones. Then compare size against a coin: a US penny is 19 mm across. Our bug identifier tool does this filtering for you.
The 10 bugs
Kissing Bug
Kissing BugTriatoma sanguisugaA cone-nosed assassin bug with orange-red markings around the edge of its flat abdomen. It feeds on the blood of animals and people, sometimes biting near the face at night.
Tell-tale sign: Elongated, cone-shaped head. Risk: Kissing bugs can carry the parasite that causes Chagas disease; save the bug and contact your health department if you are bitten.
Bed Bug
Bed BugCimex lectulariusA flat, oval, apple-seed-sized insect that hides in mattress seams, bed frames and furniture and feeds on human blood at night. Infestations spread through luggage, used furniture and shared walls.
Tell-tale sign: Flat, oval, reddish-brown body without wings. Risk: Bed bug bites itch and cause stress and sleep loss, but bed bugs are not known to spread disease.
Wheel Bug
Wheel BugArilus cristatusA large, gray assassin bug with a raised, toothed crest on its back that looks like half a gear wheel. It hunts caterpillars and beetles and is a garden ally.
Tell-tale sign: Semicircular, cog-like crest on the thorax. Risk: Its bite is extremely painful and can take days or weeks to heal, so avoid handling it.
Aphid
AphidAphidoidea superfamilyA tiny, soft, pear-shaped insect that clusters on new shoots and leaf undersides to suck sap. Aphids reproduce quickly and leave sticky honeydew that attracts ants.
Tell-tale sign: Pear-shaped, soft body, often green or black. Risk: Aphids don't bite people; heavy colonies curl leaves and spread plant viruses.
Boxelder Bug
Boxelder BugBoisea trivittataA black bug with red-orange lines on its back that feeds on the seeds of boxelder and maple trees. Large groups sun themselves on warm walls in fall before crawling inside.
Tell-tale sign: Black body with three red lines on the thorax. Risk: Boxelder bugs rarely bite and are harmless, but their droppings can stain curtains.
Brown Marmorated Stink Bug
Brown Marmorated Stink BugHalyomorpha halysA shield-shaped, mottled brown bug that invades homes in fall to overwinter and feeds on fruit and vegetables in summer. It releases a sharp odor when disturbed or crushed.
Tell-tale sign: Shield-shaped, marbled brown body. Risk: Stink bugs don't bite or sting people; they are a household and crop nuisance.
Squash Bug
Squash BugAnasa tristisA flat, grayish-brown bug that sucks sap from squash and pumpkin vines, causing leaves to wilt and turn crispy. Clusters of bronze eggs appear on leaf undersides.
Tell-tale sign: Flattened, dull gray-brown body. Risk: Squash bugs don't harm people; they can wipe out squash and pumpkin plants.
Western Conifer Seed Bug
Western Conifer Seed BugLeptoglossus occidentalisA long, brown bug with flattened, leaf-like expansions on its hind legs. It feeds on pine cones in summer and wanders indoors in fall, buzzing loudly when it flies.
Tell-tale sign: Leaf-shaped flat widenings on the hind legs. Risk: Western conifer seed bugs don't bite or sting; they may release a pine-like odor.
Large Milkweed Bug
Large Milkweed BugOncopeltus fasciatusA bright orange-and-black bug that feeds on milkweed seeds in clusters of adults and nymphs. Its colors warn predators that it tastes bad.
Tell-tale sign: Orange body with a black band across the middle of the back. Risk: Large milkweed bugs are harmless to people and don't damage garden crops.
Periodical Cicada
Periodical CicadaMagicicada septendecimA black cicada with red eyes and orange wing veins that emerges by the millions every 13 or 17 years. Males fill forests with a loud, pulsing chorus.
Tell-tale sign: Black body with bright red eyes. Risk: Cicadas don't bite or sting; egg-laying can damage branch tips on young trees.
Which ones should you worry about?
3 of the 10 bugs in this guide can bite or sting. The ones to take seriously are kissing bug. The rest are harmless or simply a nuisance.
Comparison at a glance
| Kissing Bug | Bed Bug | Wheel Bug | |
|---|---|---|---|
| Group | True Bugs | True Bugs | True Bugs |
| Scientific name | Triatoma sanguisuga | Cimex lectularius | Arilus cristatus |
| Size | 15–25 mm | 4–7 mm | 25–38 mm |
| Colors | Black, Red and Orange | Brown and Red | Gray and Brown |
| Legs | 6 legs | 6 legs | 6 legs |
| Wings | Yes | No | Yes |
| Bites or stings | Bites | Bites | Bites |
| Risk | Health risk | Can bite or sting | Can bite or sting |
| Key feature | Elongated, cone-shaped head | Flat, oval, reddish-brown body without wings | Semicircular, cog-like crest on the thorax |
Frequently asked questions
What is the most common one?
Among the bugs in this guide, the kissing bug and bed bug are the ones people ask about most.
Which of these are dangerous?
Kissing Bug can be medically significant.
How can I identify a bug I found?
Use the free bug identifier tool: choose the number of legs, wings, main color, size and where you found it, and it will list the closest matches.