Dolomedes schauinslandi

This species was described in 1899 by Eugène Simon from female specimens. It was most recently revised in 2010. One of the syntypes is stored in Senckenberg Museum under registration number 9904979-RII/4979-137.{{Cite web |title=SeSam - Forschungsinstitut Senckenberg |url=http://sesam.senckenberg.de/page/index.asp?objekt_id=15997&sprache_kurz=en |access-date=2024-10-06 |website=sesam.senckenberg.de}}

This large Dolomedes spider has been described as "one of the biggest and most robust species of the genus Dolomedes". This species demonstrates sexual dimorphism, with male body lengths of {{convert|18.6|–|26.0|mm}} and females of {{convert|23.3|–|30.2|mm}}. Both males and females are substantially larger than other New Zealand Dolomedes species. The carapace and legs are red-brown with orange stripes on the centre and sides of the abdomen.{{cite journal|last1=Vink|first1=C.J.|title=Fauna of New Zealand Pisauridae (Arachnida: Araneae)|journal=Fauna of New Zealand|date=2010|issue=64|url=http://www.landcareresearch.co.nz/__data/assets/pdf_file/0004/49027/FNZ64VinkDuperre144.pdf|access-date=3 August 2017|archive-date=22 May 2017|archive-url=https://web.archive.org/web/20170522063219/http://www.landcareresearch.co.nz/__data/assets/pdf_file/0004/49027/FNZ64VinkDuperre144.pdf|url-status=dead}} They have bright eye shine and can be spotted at night from 20 metres away.{{Cite web|url=http://blog.tepapa.govt.nz/2018/04/13/giant-spiders-and-other-critters-of-rangatira-island-chatham-islands/|title=Giant spiders and other critters of Rangatira Island, Chatham Islands|last=Miskelly|first=Colin|date=13 April 2018|website=Te Papa's Blog|access-date=18 May 2018}}

D. schauinslandi is active at night in forest and scrubland habitat, where it hunts for wētā on the forest floor or tree trunks. Its predators may include mice and weka, which would explain its absence from Pitt Island, where it was described as common in the original species description. Mating has not been observed, but females have been observed carrying egg sacs in their chelicerae in November and December and guarding their nursery from December to February, as would be expected for a nursery web spider.

File:Dolomedes schauinslandi 1805950.jpg

This species, the only Dolomedes known from the Chatham Islands, is classified as having a relict population status, due to it surviving in less than 10% of its previously known habitat.{{cite journal|last1=Sirvid|first1=P. J.|last2=Vink|first2=C. J.|last3=Wakelin|first3=M. D.|last4=Fitzgerald|first4=B. M.|last5=Hitchmough|first5=R. A.|last6=Stringer|first6=I. A.N.|title=The conservation status of New Zealand Araneae|journal=New Zealand Entomologist|date=2012|volume=35|issue=2|pages=86–87|doi=10.1080/00779962.2012.686310|s2cid=84574921}} It was probably present on the main Chatham Island prior to human settlement, as it is found on mouse-free Houruakopara Island which is only 200 m offshore. The other two islands in its current range, Mangere and Rangatira, are now free of introduced mammals and have restricted access to maintain their predator-free status; Rangatira was farmed up to the 1960s, but cats, mice, and rats were never introduced there.{{cite web|title=Mangere and Rangatira islands|url=http://www.doc.govt.nz/nature/habitats/offshore-islands/chatham-islands/mangere-and-rangatira-islands/|website=Department of Conservation|access-date=7 August 2017}}

The Rangatira spider was first described from specimens collected on Pitt Island, but despite substantial surveys it has not been seen there since the early 1900s. Mice, which are known spider predators, were accidentally introduced to Pitt some time before 1951, and may have driven D. schauinslandi extinct there. It is possible that this species could re-establish itself on Pitt Island, if there was suitable predator-free habitat (Pitt Island has mice but not rats); spiderlings lift their abdomens when exposed to a breeze in the lab, which is a behaviour associated with aerial travel by ballooning.

Under the New Zealand Threat Classification System, this species is listed as "Relict" with the qualifiers of "Conservation Dependent" and "Island Endemic".{{Cite journal |last1=Sirvid |first1=P. J. |last2=Vink |first2=C. J. |last3=Fitzgerald |first3=B. M. |last4=Wakelin |first4=M. D. |last5=Rolfe |first5=J. |last6=Michel |first6=P. |date=2020-01-01 |title=Conservation status of New Zealand Araneae (spiders), 2020 |url=https://www.doc.govt.nz/globalassets/documents/science-and-technical/nztcs34entire.pdf |journal=New Zealand Threat Classification Series |language=English |volume=34 |pages=1–37}} This species is vulnerable to mice.

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{{cite web |title=Taxon details Dolomedes schauinslandi Simon, 1899 |work=World Spider Catalog |publisher=Natural History Museum Bern |url=http://www.wsc.nmbe.ch/species/27336 |access-date=12 August 2017 }}

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{{wikispecies|Dolomedes schauinslandi}}

{{commons category|Dolomedes schauinslandi}}

• Rangatira spider discussed on RNZ Critter of the Week, [http://www.radionz.co.nz/national/programmes/afternoons/audio/2018645527/critter-of-the-week-the-rangatira-spider 18 May 2018]

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schauinslandi

Category:Spiders described in 1899

Category:Endemic spiders of New Zealand