Abstract
The toxicity of a number of insecticides was tested against three species of springtails (Collembola), Folsomia candida (Willem), Onychiurus justi porteri (Denis), and Hypogastrura armata (Nicolet), which were cultured in the laboratory. Treatment was accomplished by incorporating the insecticide into moist Plainfield sand and exposing the springtails for 24 h on this substrate. Generally, the order of toxicity of the insecticides to all three species was: Counter® (phosphorodithioc acid S- (tertbutylthio) methyl O,O diethyl ester) > phorate > carbofuran > heptachlor > methomyl > chlorfenvinphos. Acephate, leptophos, p, p′-DDT, and chlordimeform were of low toxicity to all species. More significantly, however, there were large interspecific differences in susceptibility to insecticides; fensulfothion was virtually non-toxic to O. j. porteri (LD50 > 80 p.p.m.) but highly toxic to F. candida (LD50 = 0.1 p.p.m.). Results of these tests suggest that extrapolation of toxicity data from one species of springtail to other species would be unwarranted.