Let's test your sex skills guys/girls..... not literally!
These are three Umbee's I have the opportunity to purchase..... I'll probably buy all three to ensure I have a pair. Let see if what you think they are.... boy or girl! (Sorry for the bad pics....)
I would take photos of the vent but I don't think the owner would be too stoke if I'm prodding his fish!
The first two pics the fish are extremely stressed in a small tank.... the last picture the fish is in a 40 gallon tank with light substrate and light background making him lighter.