Opossums are considered natural predators of snakes and possess resistance to the venom of some viperids. The resistance of Didelphis to Crotalus venom has been demonstrated through biochemical and immunological assays. However, systematic observations on the behavior of adult Didelphis preying on venomous snakes have never been conducted. In this study the predatory and defensive behaviors of Didelphis marsupialis and Crotalus durissus, respectively, were analyzed in captivity. Defensive strategies showed by snakes included immobility, flight attempts, coiling, cocking, rattling, and counterattack with strikes and bites. The most common defensive behavior of the rattlesnakes was immobility. The way the opossums attacked was classified in three categories, depending on the defensive reactions presented by the snakes. On all occasions when the opossums were bitten, the injection of venom apparently did not affect the predation. The great ability in capturing and handling Crotalus durissus together with the apparent great tolerance to the venom shown by Didelphis marsupialis when preying on these snakes confirms the existent biochemical and immunological data about the resistance of opossums to crotalic venoms. In this way our data strongly reinforce the supposition that this species is an effective snake predator in nature.

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Morphological comparisons of available types of the two snoutornamented agamids from northern Borneo, Aphaniotis ornata and A. nasuta, failed to show any substantial differences. Careful examination of original descriptions of these nominate taxa also yielded no discriminant characters. Thus, although the holotype of A. nasuta was not detected in our survey of various museum collections, we are sure that it is appropriate to synonymize this nominate species with A. ornata.

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Patterns of conspecific and heterospecific pair-formation in Rana porosa brevipoda and Rana nigromaculata were investigated in the field. In R. porosa brevipoda, most of the conspecific pairs were formed by female initiation. Size-assortative mating was observed in R. porosa brevipoda. On the other hand, most of the conspecific pairs of R. nigromaculata were formed by forced clasping by males. There was no significant correlation between the male and female sizes in amplectant pairs of R. nigromaculata. Of a total of 12 heterospecific pairs observed, 11 were pairs between male R. nigromaculata and female R. porosa brevipoda. The proximate factors of the asymmetry in heterospecific pairing are discussed with relation to the differences in the pairing patterns, body size, and the body shape between the two species. Possible impacts of the asymmetric hybridization on the two species are also discussed.

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Microhyla ornata consumed numerous ants, representing 77.1% in number and 44.6% in volume of the diet. The toad took ants in higher proportion than were present in the surrounding environment, and therefore, could be viewed as an ant specialized predator. Ants were the most numerously consumed prey in both spring and summer, while beetles and woodlice were less frequently taken in summer. Females have a larger body and wider mouth than males, and consumed significantly larger prey in maximum size than did males. However, mean prey size, and frequencies of occurrence for all prey taxa did not differ significantly between the sexes. These results suggest that the sexes do not differ in their use of food resources despite their morphological differences.

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The poorly known south-west Indian rhacophorid, Rhacophorus lateralis Boulenger, 1883, known from a unique holotype in the BMNH, is redescribed based on two adult females, from South Coorg, Karnataka State, south-western India. The species is listed in recent lists as valid, despite an attempted synonymy with Rhacophorus malabaricus Jerdon, 1870, by Wolf (1936). The species is diagnosed by the following suite of characters: skin of forehead free; dorsum dark brown with a pair of yellow lines that run from the region around the nostrils, over the eyelids, along the sides of the body, terminating in the inguinal region; small adult body size (SVL to 32.8mm). The species is illustrated for the first time.

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