How to identify false widow spider bites - reported recently in Kilkenny

It follows reports a man was bitten in Kilkenny by one of the feared spiders last month

Sam Matthews


Sam Matthews



False widow spider

Dublin, Cork and Wexford have the highest number of False Widow spiders to date - but following the story of a man in Kilkenny being bitten last month, and a number of local sightings have been reported.

Now, researchers from NUI Galway have developed the world’s first verified identification guide and symptoms checklist on how to treat bites from the False Widow spider. The study claims that the False Widow spider (Steatoda nobilis) is taking over Ireland and is an invasive species with a detrimental effect on native species. 

In early September, the Kilkenny People reported a story where a Kildare filmmaker reported being bitten by the false widow spider while working about 15km outside Kilkenny City. The man described a burning sensation, with the area around the bites becoming swollen and red.

Now, led by Dr Michel Dugon, the research team based at the Venom Systems and Proteomics laboratory in NUI Galway has been investigating novel therapeutics to develop medication to treat illnesses ranging from bacterial infection to cancer. It's the only laboratory in the world currently working on extracting venom from The False Widow spider for potential therapies. The study says that particular species is having a detrimental effect on other local species and spiders in Ireland due to their competitiveness and fast breeding nature.

The False Widow lives for five to seven years whereas most other spider and bug species in Ireland only lives for a maximum of one year. In Ireland, False Widow spiders live close to buildings and houses inhabited by people, they only survive in cities and not in rural areas.

Bites from a False Widow spider are not fatal, with identified symptoms resulting in a large swelling within three minutes of being bitten, sometimes followed by the formation of a dry necrotic wound when the swelling subside, and inflammation for a few days afterwards. The venom from a False Widow spider is a lot more powerful than the researchers expected, producing about one tenth of a millionth of a litre of venom.

“While it is extremely unlikely that a bite will ever be fatal, we do need to consider bites from False Widows as a potential health risk given the increase of this species not just in the UK and Ireland but also mainland Europe and the US," said Dr Michel Dugon, lead author of the study from the Ryan Institute at NUI Galway.

"We hope that our study will help to address some of the public’s concerns about these spiders and will provide healthcare professionals with the information required to accurately diagnose and report bites associated with the False Widow.”

Have you been bitten by a false widow spider in Kilkenny? If so, please get in touch with the Kilkenny People on Facebook or by emailing