A remarkable example of suspected Batesian mimicry of Gaboon Vipers (Reptilia: Viperidae: Bitis gabonica) by Congolese Giant Toads (Amphibia: Bufonidae: Sclerophrys channingi)

摘要

Batesian mimicry is a phenomenon in nature whereby a non-toxic animal emulates a noxious one, seeking to deter predators by deception. This type of mimicry occurs in many animals, with numerous documented examples of invertebrates, harmless squamates, and even birds that mimic venomous snakes. However, no observations of anurans mimicking venomous snakes have been reported. Based on comparative data from colour pattern, morphology, geographic distribution and behaviour, we propose that the Congolese Giant Toad (Sclerophrys channingi), endemic to Democratic Republic of Congo, is a Batesian mimic of the geographically widespread Gaboon Viper (Bitis gabonica). Although the colour pattern similarity between these taxa is not an exact match, aposematism and precise imitation are not required for Batesian mimicry to be effective, especially when the model (B. gabonica) is dangerously venomous and carefully avoided by other vertebrates. Given the morphological similarity between S. channingi and two other African toad species (S. brauni and S. superciliaris) that are sympatric with B. gabonica and its sister taxon (B. rhinoceros), similar examples of Batesian mimicry are likely.