Adding to Geoff's comments:
The males will definitely have nuptial pads. It usually takes males about a year to become sexually mature, females about 9 months. Females are larger wth cloacal lips. Sexually mature females have a plump, pear shaped body, males are more skinny. This is one of the few species where both males and females call. There is a subtile distinction in their voice patterns. I have identified, recorded and created sonograms of the most common calls. You will really enjoy having ACFs, they are my very favorite frogs!