The World's Most Venomous Caterpillar: The Lonomia Obliqua

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Lonomia caterpillars are one of the few venomous caterpillars on Earth and are the most deadly of all caterpillars

The Lonomia is a family of moths found in South America. There are 14 different species of Lonomia Moths. The most dangerous is the Lonomia Obliqua. They are most common in Southern Brazil. As caterpillars, these moths are highly venomous. They kill about three people a year. The anticoagulant properties of their venom are of great interest to the Medical community. There are hundreds of published studies on their venom. It has been proven to stop life-threatening blood clots in people. Scientists are working on learning the chemical makeup of the venom so they can develop medications from it.

Lonomia caterpillars are found on trees and plants. People inadvertently rub against them as they pass by. To touch one of these caterpillars can cause pain, skin rash and bleeding. Unfortunately, most people do not touch just one. Lonomia caterpillars tend to group together and normally a human touches several at once. Combined, their venom packs quite the kick. It can cause internal haemorrhaging, severe pain and rashes, kidney failure and both in-vivo and in-vitro hemolysis. It can also cause death. The symptoms caused by the Lonomia caterpillar’s venom are called Lonomiasis. The human fatality rate by these caterpillars is 1.7 percent. Interestingly, the fatality rate by rattlesnake bite is 1.8 percent. The Lonomia caterpillar has far more potent venom than the rattlesnake as they only use 0.001 percent of what a rattlesnake uses. Thankfully, scientists created anti-venom for these caterpillars in 1990.

Lonomia caterpillars have dark coloured bodies and are covered in hair. Their colouration allows them to blend into the tree bark so they are almost invisible. They grow about one to two inches long and their hairs sticks out in one-inch spikes. Once they morph into moths, they are no longer venomous. As moths, they are only a couple inches long and have dull brown mottled wings. Their wing colouration helps them blend into their surroundings, keeping them safer from predators. They eat plants and tree leaves.

Lonomia caterpillars are one of the few venomous caterpillars on Earth and are the most deadly of all caterpillars. It is interest that they can be so deadly while in their caterpillar stage, yet transforms into something gentle and harmless. For all those who vacation in South America, take extra care whenever you venture near vegetation, especially trees. One wrong step and you could be spending your vacation in the hospital instead of sightseeing.


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