Spiders questions

Water spider build diving bell webs which are used for digesting prey, although only the female's larger bell is used for mating and raising offspring. Females spend most of their time within their bells, darting out to catch prey animals that touch the bell or the silk threads that anchor it and occasionally surfacing to replenish the air within the web. The bells built by males are typically smaller than females and are replenished less often. Mating takes place in the female's bell.

According to Guinness World Records the Brazilian wandering spider is officially the world’s most venomous spider. It is capable of injecting a powerful neurotoxin which is nearly 20 times more deadly that that of the Black Widow spider if it gets into the blood stream. That is as potent as the venom of many deadly snake species and the effects are similar. The symptoms of envenomation include a loss of muscle control leading to breathing problems which can result in complete respiratory paralysis and eventually asphyxiation.

Darwin's bark spider is an orb-weaver spider that produces one of the largest known orb webs, with bridge lines spanning up to 25 metres (82 ft). The spider was discovered in Madagascar in the Andasibe-Mantadia National Park in 2009. Its silk is the toughest biological material ever studied, over ten times tougher than a similarly-sized piece of Kevlar.

A spider web is a device created by a spider out of proteinaceous spider silk extruded from its spinnerets, generally meant to catch its prey. Spider webs have existed for at least 100 million years, as witnessed in a rare find of Early Cretaceous amber from Sussex, southern England. Many spiders build webs specifically to catch insects to eat. However, not all spiders catch their prey in webs, and some do not build webs at all.

The velvet spiders are a small group of almost totally Old World spiders. The characteristics of this family of spiders are that they are entelegyne, eight-eyed araneomorph spiders that build unkempt webs. Some species are nearly eusocial, lacking only a specialized caste system and a queen.

The zebra back spider is a common jumping spider of the Northern Hemisphere. Like other jumping spiders it does not build a web. It uses its four pairs of large eyes to locate and stalk its prey before pouncing on it. Their common name refers to their vivid black and white colouration.

The female wasp named tarantula hawk captures, stings, and paralyzes the spider, then either drags her prey back into her own burrow, where a single egg is laid on the spider’s abdomen. Of these two, you should rather avoid the wasp, as it's sting is among the most painful of any insects, second maybe to bullet ant only.

All spiders have eight legs (while insects have six). Unlike most arthropods, spiders have no extensor muscles in their limbs and instead extend them by hydraulic pressure.