Spiders of New Zealand

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{{Use dmy dates|date=February 2025}}{{Use New Zealand English|date=November 2024}}

File:Beach katipo.jpg spider under a piece of driftwood]]

New Zealand has an estimated 2,000 species of spiders,Paquin, P.; Vink, C. J.; Dupérré, N. (2010). [https://wsc.nmbe.ch/reference/11514 Spiders of New Zealand: Annotated Family Key & Species List]. Manaaki Whenua Press, Lincoln, New Zealand, 118 pp. with over 1,100 species described scientifically.{{cite web |last=Manch |first=Thomas |title=A guide to New Zealand's spiders: The good, the bad and the ancient |url=https://www.stuff.co.nz/national/85713837/a-guide-to-new-zealands-spiders-the-good-the-bad-and-the-ancient |website=Stuff |access-date=21 September 2021 |date=25 October 2016}} Over 90 per cent are endemic, with the approximately 70 non-endemic species being introduced through association with humans or by natural processes such as ballooning.{{cite web |title=Spiders |url= https://www.landcareresearch.co.nz/discover-our-research/biodiversity-biosecurity/plants-invertebrates-fungi-and-bacteria/invertebrate-systematics/spiders/ |publisher=Landcare Research |accessdate=20 March 2025}}{{cite web |title=Spiders – destination New Zealand |url= https://collections.tepapa.govt.nz/topic/8180 |work= |publisher=Museum of New Zealand Te Papa Tongarewa |access-date=20 March 2025}}

The New Zealand spider with the largest leg span is the Nelson cave spider (Spelungula cavernicola), with a leg span of up to {{convert|13|cm|in}} and a {{convert|3|cm|in}} body length.

The flat huntsman spider (Delena cancerides), called the Avondale spider in New Zealand, was accidentally introduced from Australia in the early 1920s, possibly in shipments of hardwood logs used for railway sleepers.{{cite journal |last1=Rowell |first1=D. M. |last2=Avilés |first2=L. |date=1995 |title=Sociality in a bark-dwelling huntsman spider from Australia, Delena cancerides Walckenaer (Araneae: Sparassidae) |journal=Insectes Sociaux |volume=42 |issue=3 |pages=287-302}} It is considered harmless to humans, and individuals have been collected for use in at least two films.

Very few New Zealand spiders have bites that can cause significant injury to humans, and of these, only one – the katipō – is endemic. Katipō bites have been known to cause systemic effects, such as hypertension, seizure, or coma, though no deaths as a result of katipō bites have been recorded for over 200 years. Its more dangerous close relative, the venomous Australian redback spider, has established a foothold in some parts of New Zealand, notably in Taranaki and Central Otago.{{cite journal | url=https://link.springer.com/article/10.1007%2Fs10530-010-9885-6 | doi=10.1007/s10530-010-9885-6 | title=The invasive Australian redback spider, Latrodectus hasseltii Thorell 1870 (Araneae: Theridiidae): Current and potential distributions, and likely impacts | date=2011 | last1=Vink | first1=Cor J. | last2=Derraik | first2=José G. B. | last3=Phillips | first3=Craig B. | last4=Sirvid | first4=Phil J. | journal=Biological Invasions | volume=13 | issue=4 | pages=1003–1019 | bibcode=2011BiInv..13.1003V }} The Australian white-tailed spider, first recorded in New Zealand in 1886, has been falsely attributed as the cause of many necrotising spider bites.Rademaker, M.; Derraik, J. G. B. (2009). [https://www.researchgate.net/publication/281022313_White-tail_spider_bites White-tail spider bites]. ACC Review 42: 1-2.