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Amphibian defence mechanisms commonly rely on cutaneous toxins produced in either isolated or clustered glands, such as toad parotoid macroglands. In contrast to the passive mechanism of poison liberation in other amphibians, we discovered that the Amazonian toad Rhaebo guttatus is unique because it can voluntarily squirt jets of poison from its parotoids. Amphibians commonly use toxic, cutaneous se-cretions produced by glands spread over the body as a defence against predators (Duellman and Trueb, 1994). In bufonids, these glands are grouped behind the eyes, forming a pair of pos-torbital structures, known as parotoid macrog-lands (Toledo and Jared, 1995; Tyler, Burton and Bauer, 2001). Amongst amphibians, toads provide a classic example of passive defence, based on contact between a predator's oral mu-cosa and cutaneous poisonous secretion. When threatened, they react by inflating their bodies in such a way that the parotoids become turgid and primed. When an aggressor bites a toad, it becomes the agent of its own poisoning by trig-gering the macroglands and, consequently, re-ceiving jets of poison in its mouth (Jared et al., 2009). The activation of the amphibian's chemi-cal defence usually seems to be dependent on predator's bites (Jared et al., 2005, 2009; Toledo and Haddad, 2009; Heiss et al., 2010). Here we