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Multicellular glands in the amphibian integument represent a significant evolutionary advance over those of fishes. Bufonids have parotoid glands, symmetrically disposed in a post-orbital position. Their secretion may contribute to protection against predators and parasites. This study provides a re-evaluation of the morphology of the Bufo ictericus parotoid glands. The parotoid gland integument of the medial surface shows rounded depressions with small pores that connect with the duct openings of the larger granular glands. Under light microscopic evaluation the integument is constituted by typical epidermis, supported by dermis subdivided into a spongious dermis, a reticular dermis, and a compact dermis. The Eberth-Katschenko layer is identified as a basophilic material scattered throughout the superficial spongious dermis. The parotoid gland is an integument region, in which three exocrine glandular types occur: mixed glands, smaller granular glands and larger granular glands. The mixed gland is formed by mucous and serous cells while the small granular glands contain a homogene acidophilic intake. The larger granular glands produce a basophilic and alcianophilic material, and are responsible for the macroscopic protuberances designed as parotoid glands. Thus, the end product released by the parotoid glands is a mix of secretions produced by the three glands.

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Besides other pathogens, the chytrid fungus Batrachochytrium dendrobatidis has been considered the main etiologic agent that causes chytridiomycosis and associated with amphibian die-offs. Chytrid fungus was first described in a living specimen of a Physalaemus signifer population (Anura, Leiuperidae), a common frog in natural environment in Rio de Janeiro, Brazil. The P. signifier integument is formed by a poorly keratinized epidermis supported by a dermis, which is subdivided into a spongious and compact layers. The granular and mucous glands are located in the spongy dermis. Although P. signifer showed no macroscopic lesions, microscopic analysis revealed hyperkeratosis (epidermal disruptions associated with thickening of horny layer), and some oval to spherical sporangia in the horny layer. The occurrence of chytrid fungus indicates that this pathogen is still active in Brazilian anurans and can be spreading. Considering the few sporangia in the epidermis and the strong epidermal disruption, the results suggest that the integument lesion occurs before the colonization by the chytrid fungus. Thus, the chytrid may be an opportunist fungus and not the main cause of amphibian decline.