It has long been thought that while some reptiles are able to secrete venom from their mouths, this is not the case for amphibians. However, according to a new study, at least one of the latter members may have fatal bites. It is an unusual animal found in the tropics of Africa, Asia, and the Americas — although they are amphibians, they look more like snakes or pythons.
And scientists recently discovered that a special crucible called Siphonops annulatus secretes a toxin through the glands of the tail skin. This is probably a defensive measure designed to prevent predators from following it into the caves in which it lives. But now, scientists in Brazil and the United States have discovered that Siphonops annulatus has tiny fluid-filled glands in its upper and lower jaws. Long pipes run from each of these glands to the bottom of each tooth of the animal.
“Toxic skin glands are formed from the epidermis, but these oral glands are developed from dental tissue, which is the same developmental origin that we found in the venom glands of reptiles.” Pedro Luiz Mailho-Fontana, a postdoctoral fellow at the Butantan Institute in Brazil, said.
Having said that, the full chemical composition of the liquid in the oral glands has not yet been determined. However, if it is toxic, then the evolution of the glands of Siphonops annulatus may actually predate the development of the venomous mouth glands of snakes or other vertebrates.
Scientists believe siphonops annulatus is likely to have developed glands that are more offensive than defensive, using them to subdue bitten prey such as worms, termites, frogs and lizards.
The study was described in a recent paper published in the journal iScience.