This site and others indicate you can't sex a turtle until it is 4".
A juvenile has the appearance of a female: short front nails, cloaca that doesn't extend past the shell, a short tail and other indicators. Our turtle is just slightly over 3", maybe 3 1/8". It still has the appearance of a female. I'm assuming that if you can tell at 4", then there has to be some beginnings of sexual dimorphism before that.
With the understanding that you can't be certain until past 4" or more, at what point do you begin to see longer nails or the cloaca of a male begin to extend? Are there hints at 3 1/2"? At 3 3/4"?
Any input appreciated. I've seen lots of info on sexing, but little on the transformation of juvenile to adult.

