New spider species has biggest females

A female Herennia multipuncta spider can grow to be five times as large as a male of the same species. Image: M. Kuntner

Golden silk orb spiders are known for their large size and fantastic webs. Nephila komaci, the newest member of the group, is the biggest yet.

The body of the most complete female specimen is four centimetres long, with a 10 to 12 centimetre leg span.

Matjaz Kuntner, a biologist at the Slovenian Academy of Sciences and Arts, and Jonathan Coddlington, an entomologist at the Smithsonian National Museum of Natural History, believe the species might help explain why females of some animal groups are much larger than males.

As with other species in the Nephila genus and the related genus Herennia, N. komaci females can grow to be about five times as large as the males. Being bigger might help them ward off predators and have more babies.