There are worries more exotic spiders are living in our gardens, sheds or old buildings.
The creepy crawlies have been sneaking into the UK for ages in crates of fruit or plants. But now more are surviving because the weather's getting warmer here.
So how easy is it to spot these creatures? And are they dangerous? We sent Maddy on the hunt...
"We went to check out a tunnel in south London where some of the exotic spiders have already been found.
The tunnel was dark and creepy!
Even without the eight-legged creatures, I thought the tunnel was creepy enough! It was very dark, and there was mould and moss growing all over the walls.
But the exotic tube web spider loves this kind of environment because it can make a cosy, warm home in the cracks in the wall.
It's been spotted here lots in the past. Unlike British spiders this kind has got glowing green jaws.
If you approach it, its fangs come out and it raises its legs. It's body measures between 1.5 and 2.2cm.
Tube web spiders are nocturnal though, so they tend to sleep during the day and come out at night. We definitely needed an expert to help us try to track them down!
Maddy only spotted British spiders
Luckily we'd organised to meet Vicky Kindemba. She works for charity Buglife, which is committed to saving Britain's rarest little animals.
We had a bright torch and set to work scanning the walls and looking in every nook and cranny. It took ages! There were lots of webs and some small brown British spiders. But after all that effort the tube web spiders were nowhere to be seen!
I was gutted we missed them; Vicky reckons we were probably very close.
In the future it looks like it will be much easier to find exotic spiders like this though.
Hunting high and low
The weather here is getting warmer because of global warming so spider stowaways from hot countries are much more likely to survive than a few years ago.
But don't worry, most of them are from Europe and they're not dangerous. Unless it gets much, much hotter here, the REALLY scary species from the jungle and the desert will find it almost impossible to survive. That makes me a very happy girl!
Hunting for little green spiders was fun. But I'd run very, very fast if I ever spotted a tarantula in my back yard!"