New ‘giant’ Golden orb spider discovered in South Africa

21/10/2009 09:32:40 First new giant orb spider for 130 years
October 2009. We already know of, and have identified, some 41,000 spider species worldwide, and about 400-500 new species are described every year. However for some well-known groups, such as the giant golden orb weavers, Nephila, the last new species dates from the 19th century.

Largest Web-spinning spiders
Nephila are renowned for being the largest web-spinning spiders, making the largest orb webs, which is why no new spiders have been described for so long. This discovery also provided an insight into the relative sizes of male and female Nephila. To read more on this, please click PLoSONE.

First found in a museum
This is the first new Nephila species identified since 1879. The first specimen, a huge, distinctly different female collected in 1978 at Sodwana Bay in South Africa, was discovered in 2000 in the collections from Pretoria.

Illustrating the size of web that Giant golden orb-web spiders can create, exceeding 1 metre in diameter: Nephila inaurata (Photo M. Kuntner). www.nephilidae.com

Two subsequent expeditions, specifically designed to find this species, were unsuccessful, suggesting that perhaps the form was a hybrid or extinct. Then in 2003 a second, unmistakably conspecific specimen from Madagascar was discovered in a Viennese museum, thus weakening the hybrid hypothesis.

Failure to find additional specimens in more than 2500 samples from 37 museums seemed to support the extinction theory until two additional females and a male were collected in Tembe Elephant Park by South African colleagues, and it is now clear that N. komaci is a valid, new Nephila species.

Only the females of Nephila spiders are ‘giants', with a 5 inch leg span; the male spiders are tiny by comparison. Female spiders can spin webs that reach up to 1m (3ft 3in) in diameter.

Nephila Komaci was identified by Matjaz Kuntner, of the Slovenian Academy of Sciences, and Jonathan Coddington, of the Smithsonian Institution's National Museum of Natural History in USA.

To read the full scientific paper, click PLoSONE.