A black widow stretches it's legs a red spot on it's belly.

Which one of these spiders is a black widow?

The world of bugs is filled with lookalike species. Why?

A southern black widow, Latrodectus mactans, is seen at the Audubon Nature Institute in New Orleans, Louisiana. It's one of five black widow species found throughout North America. 
Photogrpah By JOEL SARTORE, NATIONAL GEOGRAPHIC, PHOTO ARK

This will get your spidey sense tingling: There’s a type of spider that looks like a black widow—but packs a much less potent bite.

False widow spiders resemble their infamous cousins, black widow spiders, with spindly legs and globe-shaped bodies. Like black widows, these species have markings on their abdomen, though not as bright red or as distinctive as the black widow’s classic hourglass shape.

The black widow possesses venom 15 times as powerful as that of a rattlesnake. Though that sounds scary, human deaths following a bite are exceedingly rare, with none reported in the U.S. since 1983. (Get a mesmerizing look at nature’s eight-legged wonders.)

The false widow is just one example of how nature has evolved lookalikes that can make it tough for people to tell one bug apart from another.

“A lot of times these insects are trying to trick us and others around them on purpose. There’s all sorts of different types of mimicry” among Earth’s 900,000 known insect species, says Julie Peterson, an entomologist at the University of Nebraska-Lincoln.

Hoverflies, for instance, have only one line of defense: By looking just like bees, with black-and-orange markings, they hoodwink predators into not attacking them.

That’s probably not a 'murder hornet' 

In 2020, an invasive insect called the northern giant hornet arrived in Washington State. Thanks to a quick-acting campaign to eradicate their nests, none of the hornets have been seen since 2022. Even still, a two-inch-long venomous insect nicknamed the “murder hornet” (after its aggressive way of attacking bees) has kept it top of mind for many. (Related: Why murder hornets are getting a new name.) 

“We get numerous emails and calls in the spring and summer,” says George Hamilton, an entomologist at Rutgers University in New Jersey, clear on the other side of the country. 

People “confuse the [invasive] European hornet and cicada killers for northern giant hornets all the time,” he says via email. (Fun fact: The U.S. has no native hornets.)

The native cicada killer is a wasp that resembles the northern giant hornet. However, the cicada killer—which rarely stings humans—has a black body with somewhat irregular yellow stripes. 

Northern giant hornets are more golden in color, with consistent stripes and pointy antennae, as opposed to clubbed ones, says Chris Looney, an entomologist at the Washington State Department of Agriculture, via email.

Since northern giant hornets were never found outside of Washington or British Columbia, it’s likely that’s something else you see buzzing by, he adds. (Learn more: ‘Murder hornet’ mania highlights dangers of fearing insects.)

Sussing out invaders

Sometimes, native insects look just like non-native insects, which can make controlling the invading species even more challenging.

Take the emerald ash borer, originally from East Asia, whose brilliant metallic green exoskeleton makes it look more like a Christmas ornament. After mother borers lay their eggs under the bark of ash trees, larvae hatch and devour the tree from the inside—a phenomenon that has destroyed millions of trees since the bug was first spotted in Michigan in 2002. (Read more about the ash borer’s impact on American cities.)

The emerald ash borer’s erstwhile twin is the six-spotted tiger beetle, also coated in shiny green, but with a wider body and longer legs. It’s a much speedier critter, too, catching and eating a variety of insects including ants, grasshoppers, and caterpillars.

The Japanese beetle has a metallic green head, copper body, and six poofs of white hair on each side, like frosting swirls on a cake. It’s also a defoliator of plants in the eastern U.S., Midwest, and some parts of the West. The invader is partial to some 300 species of plants and trees, including cherry, peach, and apple.

Their innocuous doppelgängers, ground beetles, have longer bodies than Japanese beetles, and they eat lots of agricultural pests, including slugs, aphids, and ants.

Recluse or not?

Brown recluse spiders, native to the central and southern U.S., are one of only three types of venomous spiders in the U.S. Although bites are rare, they can cause painful wounds. Being brown in color, people often get them mixed up with other spiders, particularly wolf and grass spiders, says Catherine Scott, a postdoctoral researcher in entomology at McGill University in Montreal.

Scott helps manage the Twitter page “Recluse or not?”, which encourages people to send in an unidentified spider photo and get a trustworthy answer from an expert.

A good rule of thumb: Wolf and grass spiders are much larger than the brown recluse, which is light brown and barely an inch long. Wolf spiders also have two distinct dark stripes down both segments of their bodies, and grass spiders are darker in color.

Know your ladybugs

As well as mistaken identities, Peterson has also encountered a recognition gap between ladybug, or ladybeetle, generations that leads to indiscriminate killing of the helpful insects. (Read why insects worldwide are in decline.)

Most people know the colorful, spotted adult ladybug, found in many countries, which eats garden pests such as aphids. But fewer recognize ladybug eggs, larvae, and pupae.

Ladybug eggs look a bit like gel vitamin capsules, golden and oval-shaped, bunched together on a leaf. Larvae “look like a spiky alligator with long legs,” which can be black, yellow, and orange in color, Peterson says, while pupae resemble an orange spotted grub.

Many gardeners and others often squash these eggs, pupae, and larvae, thinking something is wrong with their plant or that the young ladybugs are some unknown pest—when the exact opposite is true, she says.

“The larvae of ladybeetles focus on eating aphids and other kind of soft-bodied insects, whereas the adults can be a little bit more generalists,” she says, including pollen and nectar in their diets.

Having more knowledge about our tiny neighbors makes it easier to co-exist with them, Peterson says. And be kind. Bugs have the same goal as us—just trying to make it to another day.

Read This Next

Omega-3s are more critical for your health than we thought
New museum reckons with Charleston’s role in the slave trade
How Barbie’s signature pink took over the world

Go Further

Subscriber Exclusive Content

Why are people so dang obsessed with Mars?

How viruses shape our world

The era of greyhound racing in the U.S. is coming to an end

See how people have imagined life on Mars through history

See how NASA’s new Mars rover will explore the red planet

Why are people so dang obsessed with Mars?

How viruses shape our world

The era of greyhound racing in the U.S. is coming to an end

See how people have imagined life on Mars through history

See how NASA’s new Mars rover will explore the red planet

Why are people so dang obsessed with Mars?

How viruses shape our world

The era of greyhound racing in the U.S. is coming to an end

See how people have imagined life on Mars through history

See how NASA’s new Mars rover will explore the red planet