Theridiidae

Theridiidae spiders are a huge family of living things. People often call them tangle-web spiders or comb-footed spiders.

This group is very diverse and lives all over the world. They are the most common spiders you might find inside human homes. There are around 3,000 different species in this family. These species are split into 128 different groups called genera.

Scientists first described this large family in 1833. A man named Carl Jakob Sundevall was the one who named them.

These spiders have a very special way of working with silk. They are ecribellate, which means they spin sticky silk to catch prey. This is different from spiders that spin woolly silk.

To help them, they have a comb of tiny bristles on their fourth leg. These bristles are called setae. They use this comb to manage their silk. Many of them build gumfoot-webs to catch food. These webs use frame lines to anchor to things nearby. They also use support threads that have sticky, viscid silk on them.

Researchers use these spiders to learn many things about science. Some are model organisms, which means they are used for important studies. The widow spiders are very important for studying venom. Scientists look at how this venom affects the body.

Other spiders, like the Anelosimus, help us study sociality. This is the study of how living things live in groups. Some Anelosimus species live alone, but others live in permanent social groups. Because these social groups are highly inbred, they are also good for studying inbreeding. Scientists also study the Hawaiian happyface spider to learn about color.

There are many different kinds of webs in this family. Some spiders build tangle webs that look like messy knots. Others build webs that hang near the ground to trap ants.

These spiders use elastic, sticky silk lines that lead to the soil. These webs stay in one place for a long time. Spiders will expand and repair them instead of making new ones. Some tiny spiders called Argyrodinae live in the webs of bigger spiders. They are called kleptoparasites because they steal food from the host. They might eat the host's prey or even the host itself.

This family has many large groups of species. The largest genus is called Theridion, which has over 600 species. Another large group is Parasteatoda, which includes the common house spider in North America.

You can see how different they are by looking at their patterns. For example, the happyface spider has a yellow body with a grin. This grin looks like a smiley face or a clown face.

These spiders are part of a much bigger world of insects and arachnids. They show us how different shapes and lives can exist in one family.