Spider families and their webs

Undergraduate student, Sam Gemmell, takes a closer look at spider webs exploring how you can identify their owner without a spider in sight

Spiders are a difficult group to identify, especially in the field. However, by looking at their webs, spiders can easily be identified to family level, even if the spider is not around! Here are some commonly found webs.

Orb webs

There are a few families of spider in the UK which make these iconic webs, including the Long-jawed orb-weavers (Tetragnathidae) and the familiar Orb-weavers (Araneidae). The webs of the long-jawed orb-weavers have an empty hub; in the Araneidae, there are strands of silk within the hub.

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Long-jawed orb-weavers are easily recognised by their elongated, thin abdomens. However, some species look more like Araneid orb-weavers.  They are to be found in their webs, in their retreats, or on nearby vegetation.

The Four-spotted Orb-weaver (Araneus quadratus) is a distinctive and easy to identify species. This one is sitting in its retreat, an enclosed area lined with silk, used by the spider as a resting place. Orb-weavers will be found either in their retreats or in the main web.

Lace webs

These messy webs are made by the Laceweb spiders (Amaurobiidae). The silk is thick, woolly, and non-sticky, and appears blue when fresh. They are often found around holes in walls. The spiders hide in retreats in the holes during the day but are easily found outside at night.

Laceweb spiders have thick legs and are darkly coloured, often with a lighter coloured cardiac mark on the dorsal side of the abdomen.

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Funnel webs

These webs belong to the Funnelweb spiders (Agelenidae), which includes the familiar House Spider. The webs are spread horizontally, made of tightly packed silk, with a funnel-shaped retreat in one corner. They are most often found in buildings but can also be found in vegetation and hollows in trees. The spider is found in the retreat or on top of the sheet. They can easily be lured out of their retreats by gently tapping on the sheet!

Hammock webs

Money spiders (Linyphiidae) build hammock webs, which are horizontal, concave, and have supporting threads at the corners and underneath. They are strung up in vegetation, but some of the smallest species create them across tiny hollows in the ground. Money spiders sit on the underside of their webs.

Linyphiidae is the largest spider family in the UK. Most species are tiny and impossible to identify without use of a microscope, but this species, Drapetisca socialis, is an exception, being relatively large and distinctive.

Most spiders create webs to catch prey, but webs have many other uses, and some spiders don’t use them to hunt. Webs are often used to protect eggs and spiderlings, as is the case in the Nursery-web Spider (Pisaura mirabilis, family Pisauridae), a species which exhibits parental care.

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