Researchers have found 50 new species of insects in Thailand, and we're not talking about minute creatures here, but about large water bugs that can even eat small fish and induce painful bites on curious humans.

The team led by Robert Sites at University of Missouri, Columbia, has described 12 of the 50 new species discovered so far: six of the nasty bugs belong to the family of the water striders - scientifically named Gerridae - which present the amazing ability of propelling themselves along the water surface.

The other six species are classified in the family of the Aphelocheiridae, including "toe biters" and their relatives, which inhabit the gravel of streams, where they lurk for prey, which is stunned with a bite when located. "It's much, much worse than a bee or wasp sting. I was bitten in the pad of my little finger, and I felt intense pain all the way to my elbow for a good 30 minutes", Sites said.

When the prey is stunned, the carnivorous bugs insert a straw-like mouth sting into the victim's body which is loaded with digestive juices, liquefying all the prey's body. "After that, they suck out the juice," Sites said. Even if the bite causes a great deal of pain, it is not dangerous to humans. "From a scientific perspective, they're all cool. They feed on other insects that they can overpower in the streams. Some even eat small fish. They're pretty ferocious predators." said Sites.

"Although the bugs are related to other insects around the world, they live only in the streams and waterfalls of the Himalayan Mountain foothills-a region facing growing environmental pressures, from locals who clear forests to plant crops, then move on once the soil's resources are exhausted. It's an ongoing problem and a threat to species we haven't even discovered yet," said Sites.