Rangatira spider

Description

Dolomedes schauinslandi or the Rangatira spider is a large spider of the family Pisauridae. It is only found on South East Island (Rangatira), Houruakopara and Mangere Islands in the Chatham Islands, New Zealand. It is one of New Zealand's largest and rarest spiders. This large Dolomedes spider was first described by Eugène Simon in 1899 as "one of the biggest and most robust species of the genus Dolomedes".This species demonstrates sexual dimorphism, with male body lengths of 18.6–26.0 millimetres (0.73–1.02 in) and females of 23.3–30.2 millimetres (0.92–1.19 in). 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. They have bright eye shine and can be spotted at night from 20 metres away. 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.