These images show the silvery colour on the back and a darker pattern on the underside.

These are fairly large spiders that belong to the orb web group Araneidae. They create expansive webs above ground level that are most frequently vertical, this allows them to trap flying insects. One easily recognised sign of this type of spider is a visible zigzag of silk in the centre of the web. The spider often sits in the centre of the web where it can easily access prey which becomes stuck in the web. They pose with the head facing downwards and the legs are often in pairs giving the impression that there are only four.

The zigzag patterns are called stabilimenta and have been accredited with several possible functions including: to make the web more visible and so avoid damage by passing animals or to reflect ultraviolet light which attracts insects.

Once suitable prey has hit the web it will be wrapped in silk to immobilize it and then bitten to inject venom. This venom will paralyze the victim and also begin to liquefy the insides with protein dissolving enzymes. When the food parcel stops struggling the spider can suck out the juices and then discard the silk covered remains. If not eaten immediately it can be stored for later consumption. If the caught prey is too large it will be cut it free from the web.

The adult female is around three times larger than the male. The male will approach a female when she has just completed her final moult. This is when she reaches sexual maturity but also a moment when he is least likely to be eaten. Once mating is completed the male will retreat. The female gradually expands, heavy with eggs and around one month later she will lay several egg sacs in nearby vegetation.

The venom is not dangerous to humans. In the very unlikely case of a bite occurring there may be mild swelling and itching.

This image is of the much smaller male spider.

This species can be found through most parts of the Iberian Peninsular as well as much of the world, with the exception of the Americas.

A similar species of orb-web spider, although more brightly coloured, is the Banded Argiope (Argiope trifasciata)

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