Mrs Williamson said it felt like sharp needles digging into her thumb

Geraldine Williamson from Countess Wear, near Exeter, believes she was bitten by a false black widow which is native to the Canary Islands.

She said her thumb felt like it was "on fire" after the bite in her garden. She was rushed to hospital struggling to breathe and is now using antibiotics.

The Natural History Museum asked her to try to trap the spider and send it on.

The round spider, which is brown with pale markings, looks like its deadly black namesake but its bite is believed to be similar to that of a wasp.

Mrs Williamson said: "I was just outside the back door sweeping up some garden debris and leaves with a dustpan and brush when suddenly I felt as if my thumb was on fire with all these sharp needles digging into my thumb. "Within seconds my thumb was numb. It swelled right up and was turning black very, very fast."

Experts say the number of false black widow bites is increasing

Her arm also swelled up and became numb and her husband rushed her to hospital by which time she was struggling to breathe

She was given antibiotics and kept under observation for several hours before being sent home. She had to keep her arm in traction for three days and still has red lumps up and down her arm and feels feverish.

Mrs Williamson says she identified the spider's markings as Steatoda Nobilis from a web search.

The Natural History Museum says the number of reports of bites by this strain is increasing as the species spreads in the south and east of England.