Arachnophobes have one less reason to tremble after a group of researchers discovered a jumping spider that would prefer to hop between salad bars than juicy necks.

Thought to be the world's first known vegetarian spider, the Bagheera Kiplingi was discovered in Mexico and Costa Rica during separate field studies from four universities, including two Canadian institutions.

``They are the only spider known to feed predominantly on plant products,'' said researcher Matt Reudink, who is working on a post-doctorate degree at Trent University in Peterborough, Ont.

``There are other spiders that might occasionally take a little bit of nectar or accidentally ingest some pollen, but it's unheard of to have predominant herbivory in a spider. Most spiders get their food by immobilizing their prey and . . . essentially drinking the insides of the prey, so it's not like solid food.''

The spiders were found on acacia shrubs, which also house ants that serve as guardians for the plants. The spiders manage to evade most of the ants and receive the bulk of their energy from beltian bodies, described as ``leaf-tip structures'' that are produced by shrubs.

While the Mexico group started working on their research into the spiders in 2007, they later realized another group found similar results in Costa Rica a few years prior to their findings.

The Costa Rica group - led by Eric Olson from Brandeis University - initially didn't publish its findings because the spiders were not their primary focus at the time, but later collaborated with Mexican group to move forward with the research.

Bob Curry, who was involved with the Mexican studies, said the vegetarian spiders might relieve some anxious arachnophobes, boasting about the eight- legged creatures calming features.

``They're very cute little spiders,'' said Curry of Pennsylvania's Villanova University who is also a dual citizen with roots in Yarmouth, N.S. ``Jumping spiders have big eyes and they're a little more personable than a lot of other spiders. They have a lot of personality.

``It seems like these spiders are widespread, but as far as we know, there's no place where the spider occurs where they don't overlap with the acacias. It seems like they're dependent on (the plants).''

Although the Mexican and Costa Rican spiders display unusual diets, there are differences among the spiders found in each country, said Reudink, a former student of Curry.

In Mexico, about 90 per cent of the tiny arachnids' diets were made up of plant life, with the other 10 per cent of the diet coming from cannibalism, as well as the eating of ant larvae and other invertebrates, which Reudink described as ``very rare events compared to the eating of the beltian bodies.''

In Costa Rica, however, the spiders are a little more adventurous with their diets, with about 60 per cent of the spiders' diets made up of plant life.

Also involved in the research were Christopher Meehan - who discovered the spiders in Mexico and co-authored the report released in Monday's edition of Current Biology - and T. Kurt Kyser of Queen's University in Kingston, Ont.

Considering the ecosystems in which the spiders were found, the researchers were surprised it took so long to discover the spiders' eating habits.

``There are over 40,000 spider species described and this is the only one that's predominantly vegetarian . . . and it's happening on an ecosystem that's been studied by many researchers for years,'' Reudink said. ``All the while, there's been this spider having this unique behaviour and we haven't noticed before.

``There's so much about the natural history of some of these systems, especially in the tropics, that we're totally unaware of that might be right in front of our eyes.''

Fonte : Canada