Nephila clavata

Nephila clavata, also known as the Jorō Spider (ジョロウグモ（女郎蜘蛛、上臈蜘蛛）, Jorō-gumo), is a member of the golden orb-web spider group. The spider can be found throughout Japan except Hokkaidō, in Korea, Taiwan and China. Due to the large size as well as the bright, unique colors of the species of the female Nephila, the spider is well-favored in Japan.

Recently scientists have confirmed the first known occurrence of N. clavata in North America.

Characteristics

Nephila clavata pass winter as eggs and scatter as tiny juveniles in the spring. The female's body size is 17–25 mm, while the male's is 7–10 mm.

The web of female Nephila can reach one meter in width; the yellow threads appear rich gold in sunlight. The structure of the web seen in cross section is unusual for an orb web; it has 3 layers: the central orb, plus 2 irregular layers in front and behind the orb.

The adult female individual has stripes of yellow and dark blue, with red towards the rear of the abdomen. In autumn, smaller male(s) may be seen in the female's web for copulating. After mating the female spins an egg sack on a tree, laying 400 - 1500 eggs in one sack. The life cycle ends by late autumn or early winter.