Black Widow vs Tarantula (Similarities and Differences)

Some of the main differences between black widows and tarantulas are that tarantulas are hairier and larger than black widow spiders. The tarantula usually also has thicker legs and although the colors of the tarantula species vary, the black widow will usually be darker than tarantulas.

The black widow spider, also called Latrodectus, is one of the most dangerous spiders in the world. That’s because of its potent venom. it’s quite easy to distinguish a black widow spider from other species by looking at its abdomen.

It has that typical red hourglass-like shape on its abdomen painted on a black body.

In this article, we’re going to take a look at black widow vs tarantula – what are the similarities and differences between the two species, and more.

Black Widow vs Tarantula

Disclaimer: This is information for entertainment and educational purposes only. Do not approach a wild animal and keep your distance. Only professionals should handle wild animals. Seek professional help immediately if you have been bitten or otherwise harmedConsult your local wildlife authority for the right advice for your situation and locality.

Similarities Between Black Widows and Tarantulas

Let’s take a look at some of the similarities between black widows and tarantulas:

1. Habitat

many tarantula species share their habitat with the black widow. Most tarantulas live in warm habitats such as the Mediterranean and southern states of the United States, but also in some countries in South America and Africa. The black widow also prefers a warm climate, similar to the tarantula.

Related Article: Black Widow Spiritual Meaning & Symbolism

2. Diet

Black widows and tarantulas have a similar diet. Both eat an insect-heavy diet, as they like to hunt down their prey and eat it. They are both venomous, although the venom of a black widow is more potent than that of the tarantula.

In the wild, many tarantulas even eat their own mates after mating.

3. Behavior

Both black widows and tarantulas are aggressive towards other spiders or potential opponents in their habitat. However, they are also both scared of humans and will flee if they spot you in the wild.

Tarantulas are often kept as a pet, so they may be able to get used to you to some extent if they are raised in captivity.

Read More: Can You Train a Spider?

Do not ever approach a potentially dangerous spider or tarantula in the wild. Even if it looks tame, some spiders carry potentially fatal venom and may act aggressively if you frighten them.

Differences Between Black Widows and Tarantulas

There are clearly some similarities between black widows and tarantulas, but they are almost exact opposites to each other within the spider world. Let’s explore the main differences between these two species.

1. Size

Tarantulas are much larger than black widow spiders. The tarantulas can grow from 4.5 inches to up to 11 inches in size (between 12 and 28 centimetres). On the other hand, the black widow spider is much smaller. It will only grow to up to 0.39 inches in size (which is about 10 millimetres).

Tarantulas are some of the largest spider species out there.

2. Hair

The second large difference between these two species is the hair. The tarantula is covered in large urticating hairs on its legs and body, which it uses for self defense and navigation. In contrast, the black widow looks almost bare, although you can still see its hair under a microscope.

For the tarantula, these hairs are very important. Not only will the tarantula use these hairs for self-defense, but it will also use them to sense its surroundings. With the help of the hair on their legs, the tarantula can sense vibrations around it, allowing it to spot other animals with ease.

Related Article: 8 Tasty Animals Black Widow Spiders Eat

3. Colors and Appearance

Another good way to distinguish between a tarantula and a black widow spider is to take a look at the colors of the species.

The most prominent feature on a black widow’s body is the red hourglass-like shape on its abdomen, while the tarantula doesn’t have this feature at all. The tarantula is usually a one-color species, although these colors can vary from one tarantula species to another.

The colors of tarantula species vary from black, brown, grey, to even brighter colors, and sometimes, they have a mixture of colors on their body. However, you will never see a tarantula with that hourglass shape, while the black widow will never have as many hairs as the tarantula.

4. Aggressiveness

Old-world tarantula species are more aggressive and less friendly to humans when compared to new-world tarantulas. However, the black widow is sometimes seen as a bit more aggressive to humans than tarantulas, causing problems to humans more frequently.

That being said, the black widow tends to shy away from humans in the wild. Even though it might be more inclined to attack you when you get close to it, its aggression is mostly pointed towards other species and its prey, in particular.

Which is More Venomous?

The black widow is more venomous than the tarantula, although both species carry venom and can be dangerous to humans and other animals.

The black widow is one of the most venomous spider species in the world. If you get bitten by a spider of this type, it may cause short-term consequences such as dizziness, inability to breathe, as well as more severe long-term consequences such as paralysis. On very rare occasions, untreated black widow bites can cause death (especially to children and the elderly).

On the other hand, tarantula bites are sometimes considered to be less dangerous. Although several tarantula species are still extremely dangerous and should be avoided.

Overall, black widows are far more dangerous than tarantulas. However, both types of spider can be dangerous and you should seek urgent medical attention if you think you may have been bitten by a dangerous spider.

In countries where venomous animal bites are common, there are usually antivenom shots stored and available, so it’s important to seek medical attention as soon after the bite as possible.


Black widow spiders and tarantulas are two of the most well-known spider species in the world. Many people opt to keep tarantulas as their pets, while black widows are some of the most feared spiders out there.

Sometimes, black widow bites can cause severe problems in the short and long term.

Black widows and tarantulas share some similarities, but differ in appearance, size, and behavior.

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