Well, here's the thing. I have an adult female which is about 3 1/2" Both my males are about 3" flat, and I let the 5 1/2" female go to a petstore(she tried to eat the boys).
Also, even if they are adults, I don't know how long it takes for a female to reach full size, but I *think* I read that it takes a good while. And it would make sense in the 2" difference between my two adults, and the fact that I found a very large froglet (still looked like a young froglet, but much bigger) which has to be a half year old, so I wouldn't think they matured for a good two years, the females. And keep growing after that until they reach full size at some point.
If anyone knows differently, however, I'd love to know!
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Got hips like Cinderella / Must be having a good shame / Talking sweet about nothing / Cookie I think you're Tame 