Chemical defense in the cave-dwelling millipede Brachydesmus troglobius Daday, 1889 (Diplopoda, Polydesmidae)

The troglomorphic millipede Brachydesmus troglobius Daday, 1889 (Polydesmida: Polydesmidae) secretes allomones from glands on both lateral surfaces of its body segments. The secretion was identified by gas chromatography-mass spectrometry (GC-MS) analysis with electron and chemical ionization, and was shown to be composed of a mixture of benzaldehyde, benzyl alcohol, benzoylnitrile, benzoic acid and mandelonitrile benzoate. Hydrogen cyanide was qualitatively identified by the picric acid test. This is the first identification of these compounds in a cave-dwelling polydesmid.