Hydrogen Cyanide Production in North American and African Polydesmoid Millipeds

A diversity of substances has been isolated from the defensive secretions of millipeds, including hydrogen cyanide, benzaldehyde, phenols, ,4-benzoquinones, quinazolinones, and nitrogen-co.ntaining terpenes (references in Altman and Dittmer, 973; Duffield et al., 974; M.einwald et al., 975; Smolanoff et al., 975; Wood, 974; Wood et al., 975). Hydrogen cyanide, the first of these compounds identified (Guldensteeden-Egeling, 882), has been reported from ov.er a dozen European and New World species, all members of the suborder Polydesmida (Barbetta et al., I966; Blum and Woodring, 962; Blum et al., 973; Casnati et al., 963; Davenport et al., 952, Duffield et al., 974; Eisner et al., 963; H. E. Eisner et al., 963; Hall et al., 969; Monteiro, 96). We have demonstrated hydrogen cyanide pr.oduction in four additional polydesmoid species, strengthening the view that cyanogenesis may be of widespread, if not general, occurrence within the suborder. Three of the species, dpheloria trimaculata, A. kleinpeteri, and Pseudopolydesmus branneri, stemmed from the U. S. A. (the first species was from Clifton Forge, Virginia; the other two. from Roanoke, Virginia) the ’fourth species, Astrodesnus laxus, was from Africa (Mombasa, Kenya). The animals were tested for cyanogenesis by manipulating them and gently squeezing them, while at the same time holding beside their bodies strips of filter paper impregnated with benzidine acetate-copper acetate reagent (Feigl, I966). In all instances the papers turned blue, indicating release of hydrogen cyanide vapor from their glands. In single individuals of .each of the North American species, cyanogenetic output was assayed quantitively (see .accompanying table), using the technique previously developed in our laborato.ries (H. E. Eisner et al., 1967