The false widow spider (Steatoda grossa) is often mistaken for the black widow spider (Latrodectus mactans). The latter possesses bright red abdominal markings, and it's unlikely these spiders could become established in the UK because of the frosts in the winter. The false widow spider is native to Europe; it possesses some white abdominal markings and is roughly 1cm fully grown. Like the noble false widow, this spider has received a lot of bad press and his often implicated in spider-bite claims. Many of these claims usually cannot correctly validate the species of spider, with news articles being worded in a way to scare its readers. To conclude, the British arachnological society states that being bitten is possible, however unlikely. In the case of a bite, you should only be alarmed if there is any associated swelling or ulceration. A spider bite is often compared with a wasp sting, they both cause the same symptoms and are seldom serious.