Behavioural and toxic effects of termite defensive secretions on ants

ABSTRACT. The toxicity and biological activity of the defensive secretions of ten species of neotropical termites were examined by bioassay on two species of predatory ant. Pseudomyrmex termitarius (F. Smith) (Pseudomyrmecinae) was more susceptible to the effects of the secretions than Ectatomma sp. (Ponerinae). The bioassay results show a progression in the nature of termite chemical weaponry and in the potency of defensive secretions. The tacky secretions used by Coptotermes and Ruptitermes are simply adhesive, entangling agents with no apparent toxic or pheromonal properties. The secretion of Syntermes calvus Emerson serves as a wound-active poison with little topical activity, while those of Armitermes spp. are repellent to ants and show activity as topical poisons. The secretions used by Nasutitermes spp. combine adhesive, entangling properties with the toxicity of a topically-active poison, and are effective also as ant-repellents.