Venomous noble false widow spider confirmed established in New Zealand

Venomous noble false widow spider now present across New Zealand

The noble false widow spider (Steatoda nobilis), one of the world’s most invasive arachnids, has officially established itself in New Zealand. First confirmed in Porirua in November 2024, the species has since been recorded in Christchurch, Nelson, Northland, and Waikato, indicating widespread urban colonization.

The spider, originally native to the Canary Islands and Madeira, has previously spread to Europe and both North and South America. According to experts, it now appears to thrive in New Zealand’s urban environments. It is commonly found in gardens, around outdoor furniture, and particularly beneath plant pots, tarpaulin, and in fence crevices. Males are typically observed at night on exterior walls or at ground level.


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Professor Steven Trewick, an evolutionary ecologist at Te Kunenga ki Pūrehuroa Massey University, led the confirmation effort. He compared physical features of collected specimens and conducted DNA analysis on a sample obtained in Porirua by Gavin Picknell.

“Although considered less dangerous than black widows, the venom of Steatoda nobilis contains similar toxins,” said Trewick. “Particularly concerning is its association with antibiotic-resistant bacteria. Infections resulting from bites don’t always respond to treatment, and that’s a significant medical concern.”

Medical risks linked to noble false widow spider bites

The noble false widow spider is venomous but not generally considered aggressive. Bites typically occur in self-defense and may cause localized symptoms including redness, swelling, and pain. However, more serious medical effects have been documented in some cases.

A spokesperson from Massey University reported that some bite incidents have resulted in tissue necrosis, nausea, hypotension, impaired mobility, and secondary bacterial infections. Notably, some of these infections may be resistant to standard antibiotics, raising concerns within the medical community.

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The spider’s venom contains neurotoxins similar to those found in black widow species, although typically less potent. Nonetheless, its presence in populated regions and proximity to human activity has prompted health and ecological monitoring.

Citizen reports aid research into Steatoda nobilis spread

Researchers encourage the public to participate in tracking the spread of Steatoda nobilis through the iNaturalist NZ platform. Suspected sightings can be uploaded with photos, enabling scientists to better understand the range and behavior of this invasive, venomous spider.

Ongoing monitoring will help assess the long-term ecological and public health implications of the noble false widow spider’s establishment in New Zealand.