Ordgarius monstrosus facts for kids

Ordgarius monstrosus is a special kind of spider that lives in Queensland, Australia. It belongs to the orb-weaver spider family, but it doesn't build a big, round web like most of them. Instead, this spider is a "bolas spider". Adult female O. monstrosus spiders catch their food in a very unique way: they use a sticky "bolas" that they swing to grab prey!

What Does It Look Like?

Imagine a spider that's about 13 millimeters long – that's a little over half an inch! The first one described in 1886 was a female. Her body, called the cephalothorax, was about 5 millimeters long. It was reddish-brown with white hairs. This part of her body also had five bumps. One bump pointed forward, and four smaller ones were behind it.

Her eyes were in two rows, curving slightly backward. The underside of her body, called the sternum, was longer than it was wide. It was yellow with some brown colors. Her mouthparts, known as chelicerae, were also yellow with brown hints.

The spider's legs were yellow with brown rings. These rings were often not fully closed. Fine white hairs covered her legs. Her first pair of legs was the longest, measuring about 15.5 millimeters.

The spider's abdomen, which is the back part of her body, was wider than it was long. It measured about 10.2 millimeters wide and 9.6 millimeters long. The top of her abdomen was yellow with brown spots. It also had some unclear bands. The corners of her abdomen had clear bumps. The underside of her abdomen was solid yellow.

Who Discovered This Spider?

The Ordgarius monstrosus spider was first described in 1886. A scientist named Eugen von Keyserling gave it its name. It was the very first species he described in his new group, called Ordgarius. This group of spiders is part of a larger family called Araneidae.

How Does It Catch Food?

Like other spiders in the Ordgarius group, O. monstrosus is a bolas spider. This means it doesn't spin a traditional web to catch its food. Instead, it uses a special hunting tool. This tool is a line with one or more sticky drops on it, which is called a "bolas".

Adult female spiders usually hunt male moths. When a moth gets close, the spider swings its bolas. It uses one of its second legs to spin the sticky line. This helps it catch the moth. Scientists think that these spiders might even trick the moths. They might create a smell that is like the sex pheromone a female moth uses to attract a male. This would draw the male moths closer, making them easier to catch!