Females are larger than males and have a "pear-shaped" body, males are more slender. The "dirty hands" of the male are called nuptial pads. They help the male hold on to the female during mating (amplexus). The females have an enlarged cloaca.

Unlike most species of frogs, both sexes call. I have several ACFs and I am able to distinguish who is calling. The female seems to control the duets, if the female is responsive, her call will encourage the male to continue his call. If the female is unresponsive, her call is different and the male will stop calling immediately. Be prepared for some loud duets - they are most active during the twilight hours.