Venomous frogs make use of bony spines present over their heads to transmit the poison into others, scientists said.

The scientists found two species of frogs in the country being exceptionally venomous. These frogs make use of their head spines and can cause a lot of harm, especially to humans.

“That clued us in that there was something a bit different about this frog. Amphibians have a wide selection of pores and skin toxins which were well- studied, however this kind of mechanism – transmitting the toxin as a venom – has not been discovered earlier than,” said Edmund Brodie, from Utah State University.

A tip off on the research came in when Carlos Jared, from Instituto Butantan in São Paulo, Brazil, was left injured by a frog Corythomantis greeningi in the field.

Experts said that one gram of venom from Corythomantis greeningi can kill 24,000 mice or six human beings together. Meanwhile, one of gram venom secreted by A. brunoi can kill around 80 humans. In mice the number may go up to 300,000.

The research paper was published in journal Current Biology’s August 6 issue. Brodie said that as on date, it was tough to believe that even frogs could be venomous.

In fact, the scientists were forced to wear heavy rubber gloves while handling these frogs to protect their hands from the venom. The same team of researchers has now started another study on other frog species which are presumed to be venomous.