I think is is actually around that age. Thanks for the link it is actually very useful. I tried using that visual dart sexing tool, but I got myself all confused because I convinced myself to see what I wanted to see lol. I convinced myself it was male and then female and then male and then I just didn't know.How old is it? Looks female, but I've had a male look like that till about 8-9 months, then start to develop obviously male characteristics.
Here's a pretty good article on sexing tincs:
Josh’s Frogs How-To Guides » Blog Archive » How to Visually Sex Dart Frogs