ABSTRACT
An efficacious antipredatory mechanism of amphibians involves the secretion of poisons and sticky products from the cutaneous glands. The defensive skin arsenal provided by the granular glands of the neotropical poison arrow frogs of the family Dendrobatidae (Daly et al. 1978; Neuwirth et al. 1979; Myers and Daly 1983; Daly et al. 1987; Erspamer 1994) is well known. The parotoid glands, which also produce defensive toxins, occur in some anurans (pelobatids and bufonids; Fig. 6.5A) as well as in several families of urodeles, including ambystomatids, plethodontids and salamandrids (Fig. 6.5B). Parotoid glands are serous in nature and look like other dermal granular glands except for their relatively larger size (Hostetler and Cannon 1974; Cannon and Hostetler 1976).
