The National Poisons Information Centre has issued a warning for to be mindful of the increased incidence of the “False Widow” spider in Ireland, especially as the winter approaches.
The False Widow (Steatoda nobilis) is a spider often confused with the deadly Black Widow spider, due to their similar appearance. The False Widow is native to Madeira and the Canary Islands, but has gradually travelled across mainland Europe and was first reported in Ireland in 1997.
Since then, the spider has become more abundant in Ireland and is a relatively common, invasive species. The False Widow has a brown bulbous abdomen with cream coloured markings that are often likened to the shape of a skull. Their legs are reddish-orange and range is size from 7 mm to 14 mm – the females are generally larger.
Unlike the true Black Widow, which has a potentially fatal bite, the False Widow’s bite is far less dangerous. However, they are the only spider species in Ireland capable to inflicting a painful bite to humans. The False Widow’s venom is often described as feeling like a wasp or bee-sting, and symptoms include a bruise or reddening at the site, swelling, and moderate pain, which usually dissipates after 12 or so hours. Serious complications only occur if the wound is infected. Medical attention is usually only necessary in the case of a severe allergic reaction, or if bitten on or around the eye.
Thankfully, the False Widow is not an aggressive species, and usually only bites when threatened or when pressed up against the skin, accidentally.
As temperatures drop, the spider is more likely to enter homes for warmth, so the public is asked to be vigilant, especially in conservatories and around windows, and to keep an eye on children’s nurseries, bedrooms, and play areas.
