In a recent paper by D. Poth et al, a novel form of communication using volatile pheromones is described for a subfamily of frogs within Mantellidae. Amphibians communicate using vocal, tactile and visual cues but may also use pheromones. Usually these pheromones are peptides or proteins and are used in the water to illicit a response. In many cases, these pheromones have been examined and their individual elements have been isolated.
In the subfamily Mantellinae, the males have femoral glands on their thighs which is suggestive of pheromone communication. In light of this, the authors removed the glands of several animals to isolate the individual compounds.
They isolated two nonpeptidic volatile compounds and one was identical to a defensive secretion from an Australian beetle (Phoracantha synonyma). Furthermore, the authors tested the behavior of conspecific frogs in response to the the two compounds and found they were sufficient to elicit body position changes.
Finally, several other species of mantellas were tested and they found in each case a species-specific mixture of compounds within the femoral gland. This is indicative of pheromone use for conspecific recognition and communication.
If one could add another experiment to this paper it would be compelling to the functional argument to examine the response of non-conspecifics vs. conspecifics to pheromones.
D. Poth, K.C. Wollenberg, M. Vences, S. Schulz Angew. Chem. Int. Ed. 2012 51