Fig. 1From: Love bites: male frogs (Plectrohyla, Hylidae) use teeth scratching to deliver sodefrin precursor-like factors to females during amplexusPlectrohyla sagorum traumatic mating. A Male P. sagorum pressing his lips on the female´s head during amplexus. Female skin before (B) and after (C) the male scratched over her head. White arrows are indicating some of the scratches. D Pointed teeth of the male, which are protruding through the swollen lips (E; pointed out by white arrows). Comparing the position of the males’ head in (A) and (B) emphasises the movement of his lips over the females’ dorsumBack to article page