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The spider with NIGHTVISION goggles: Arachnid uses its enlarged eyes to help it hunt prey on the ground at night

Deinopis spinosa spiders possess the largest eyes of all arachnids
The eyes enable them to be good at hunting prey on the ground at night
Prey on the ground is higher in nutrients and not avaiable to other spiders
Hunting at night also helps protect the spiders from predators themselves

Published: 23:04 GMT, 17 May 2016 | Updated: 00:45 GMT, 18 May 2016

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Most spiders have a cluster of eight eyes that help them target and capture their prey.

But staring out like two huge black holes, two of the ogre-faced spider's eyes have become abnormally enlarged.

Now a new study has revealed these huge peepers allow the spider, also known as Deinopis spinosa, or net-casting spider, to hunt for prey at night.

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The Deinopis spinosa (pictured) spider has the largest eyes of all known arachnids. Its prevailing posterior median eyes are just two of eight eyes, but allow it to pinpoint prey on the ground in the dark, according to new research

The Deinopis spinosa spider has the largest eyes of all known arachnids.

While at a glance they appear to have just two eyes, they actually have eight eyes like other species, but the large posterior median eyes are extremely enlarged.

Researchers has long suspected the creatures may have used these to give them an edge during the hours of darkness, but a link has never been proved.

Now a news study by the University of Nebrasca-Lincoln has found that these massive eyes allow the spider to hunt its prey on the ground at night.

Other spiders tend to hunt in the air, casting nets to capture flying prey. But in the ogre-faced spider - so called due to its ugly features - it strikes its insect prey from the front.

The spiders' extraordinary vision system helps it do this.

THE HIGH SPEED SPIDER

The trap jaw spider may be diminutive, but what it lacks in magnitude it makes up for in speed.

High speed videos have revealed the lighting fast reactions of Mecysmaucheniid spiders, which live on the ground in New Zealand and parts of southern South America, where they ambush prey among the leaf litter.

The trap door arachnid, measuring just 2mm across, can snap its jaw shut on unfortunate prey in 0.1 milliseconds - but how it's so speedy is a mystery.

As prey that live on the ground, such as crickets, tends to be bigger, it tends to also be of higher nutritional value to the spider.

This sort of prey is normally out of reach for most web-building spiders.

The researchers also concluded that the nocturnal spider's enlarged eyes allow them to remain active solely at night, avoiding numerous predators in the day.

Predators that inhabit the spider's surroundings during the day include song birds, parasitoid wasps and jumping spiders.

The researchers think the risk of being eaten or parasitised by predators in the day has played a huge role in their evolution.

The spiders were tested the spiders by conducting both field and laboratory foraging trials.

Writing in the journal Royal Society Biology Letters, Jay Strafstrom, a biologist at the University of Nebrasca-Lincoln and his colleagues who conducted the research, said: 'We have shown that a nocturnal predator heavily invested in low-light level vision through extreme sensory structures receives significant benefits from these specializations in the form of more and potentially higher quality prey.'

The ogre-faced spider was found to primarily strike its prey using a forward strike, using its enlarged eyes to help it locate and pinpoint insects on the ground