How to Spot a False Widow Spider

Around our houses, we may find different types of insects. Some of them are more dangerous than others, some like black widows. You may be surprised that these insects can appear near your house, and even see them in your house. However, once this happens you really must make sure is that type of arachnid, since there are copycats to what black widows are. This group is formed by different species of insects that have similar characteristics that resemble one of the most venomous arachnids in the world.

We’re going to help you spot the small differences and details in order not to panic when you find out that there are these kinds of bugs in your house.

What do Black Widow look like?

First, you need to know how does a Black Widow look like. Regarding size, they are small, depending on the gender, usually females are a bit larger. Their main characteristic is that they have an hourglass shaped ventral surface, typically red. Males can also have several red stripes along their bodies. They’re usually brown when they’re starting to develop, but once their grown they have a shiny black colour which stands out.

What do False Black Widows look like?

You must know that it is not only one type of spider, but these are formed by a group of them. However, most of them have basic similarities that can make you think these are real black widows. Regarding colour, they all are brown or black, reaching up to 32 mm (size of a small fingernail) including their legs. As black widows have an hourglass on their abdomen, these types can also have markings like that, but rather having a shape, they have white or lighter bands around them among other special markings that each individual species has. Sometimes you might not even find them at all since some of them fade or are just missing, especially in grown adults. Also, their behaviour might vary between species. Here we have the most common species you’ll find in the UK

Noble False Widow (Steatoda Nobilis)

Steatoda Nobilis

It is one that share the most resemblance with a real Black Widow. They can reach up to 32 mm, including their legs and are oval shaped with a very shiny look to it. Instead of having red markings, they have cream markings on their abdomen and their legs are reddish or orange.

Another of their characteristics is that they don’t tend to have nests around your house, but they tend to create webs for them to catch their prey, which really contributes to humans as pests like mosquitoes are their favourite meal, which decreases the chances of getting diseases by their bites.

In terms of behaviour, they will try and get to the highest place possible and there start hunting their prey. It is very uncommon to see one of them near humans as they’re not interested in them. Nonetheless, they can inflict a painful bite when they seem to be cornered, squashed, or must act upon an aggression they’ve received. If you get one of their bites, it is not going to be dangerous at all, you might only need to use some ointment and try to cover the bite. Use ice packs to reduce the swelling. You might feel a little bit of pain and some itching, but nothing out of the ordinary.

False widow spider (Steatoda Paykulliana)

Steatoda Paykulliana

This one look pretty like a real black widow as they have a very scandalous band on their abdomen almost identical to the red hourglass shape on a black widow’s, but this one is bright yellow. Sometimes the pattern can be orange, red or white. They’re very little as they reach up to 13 mm in length and if you find them in the UK is because they have been imported from the Mediterranean as they aren’t a very common species. They tend to hide under rocks and not live near humans.

Cupboard spider (Steatoda grossa)

Steatoda grossa

These types of false widow spiders have taken over the UK. It is common to find them in houses, especially in places that are dark and damp. Sometimes, they might hide under furniture or low corners to find insects they can hunt and keep on feeding. Also, it won’t attack humans as they’re docile and only focus on their prey. Regarding appearance, they stray away a little from what a black widow looks like. They reach up to 10 mm and on their abdomen, they tend to have markings though most of them are missing or faded in the darkest specimens.

Rabbit Hutch spider (Steatoda bipunctata)

Steatoda bipunctata

They can measure up to 7 mm and have a white band that goes from their thorax to their abdomen. This line is difficult to be seen in male specimens as it can be very light or can be missing in female specimens. Their favourite places to live are in dark areas such as pet houses, tree trunks, debris found in gardens, among others. In those places, they like to hunt and create some webs to trap their prey. They’re harmless to humans, so you won’t be in danger if one of them bites you.

False widow spiders vs Black widow spiders

Their main differences come in terms of appearance. If you see that there is a spider in your house, check if it is really a black widow before you do something about is as it might be a false one. Black widows are larger and darker than false widows. They’re brownish and have special markings that state a difference.

 Also, remember that they’re not aggressive towards humans and won’t attack unless they have been cornered or squashed, though black widows will be always vigilant towards humans and are very venomous, which their lookalikes are not, the worst thing that can happen is to get an allergic reaction.

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