I had a very big uro that looked alot like your "meaty" cute name by the way.
I was convinced that it was a male due to it's dark coloring-black and bright yellows that the male's usually have, but finally it started laying eggs!! it layed infertile eggs for 2 weeks straight and then she passed away. It drained her body and she refused food. My boy turned out to be a girl, and I was so bummed b/c I had bred beardie's but I didn't have a male mali uro 
So if you check out Doug Dix's page deerfernfarns.com he has some great pics of "male mimic" females - females that look like males
I've asked vets how to sex them and most vets don't know. you'd have to go to a licensed herpitologist- NOT a regular "exotics" vet. there's a huge difference in what they know about reptiles trust me
Kristen

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4.1 Bearded dragons (Lee,Stumpy,Blackie,Spazz,Lynn)
1 Egyptian Uromastyx (Niles)
(Papa Kunja and Uri have recently passed..we love you)
Thank you for your advice! 