The skeleton of cartilage in the tongue is shaped roughly like a pair of tweezers, with the two prongs facing the tail. Each prong is encased in a sheath of spiraling muscle fibers that, when they contract, squeeze the prongs and shoot the cartilage out of the mouth. Apparently, Wake says, the two unrelated creatures independently evolved a similar method for capturing prey . In both animals a sticky pad at the tip of the tongue immobilizes the insect until it can be brought into the mouth. Deban predicts that other members of the genus Hydromantes also use a ballistic method to protract the tongue, because all have the same tongue structure and internal cartilage.
Wake suspects that many members of the lungless salamander family do likewise.
Most members of Hydromantes live entirely on land, spending part of the year in caves or crevices, walking around on rock walls with the aid of large webbed feet, laying eggs in moist places and living off insects and other small creatures. Even before Deban's discovery they were known to have the longest tongues relative to their body of any amphibian, though none have tongues approaching the length of the much larger chameleons, members of the lizard family, Chameleonidae. These salamanders are quick with their tongues too. They can flick them out in about a hundredth of a second, much faster than chameleons, Wake says. Also, while a chameleon's tongue falls slack and is rewound into the mouth after catching a fly, salamanders jerk their tongues back.