Well it all becomes clear to me now. I have two six year old Spur thighed tortoises and cecause of the difference in size, shape and one trying to mount the other I assumed I had a male and female. She had become very aggressive to him and I have had to separate them. Whilst bathing them today I suddenly noticed what looks like a penis flashing from the tail when I picked both up. This might sound a silly question but I assume I am right and that a female would not have a pop out vagina, so I now have three males and possibly one female (I have two younger ones as well). I am so disappointed. If anyone wants to swop please let me know.

Hello,
No Fs don't have pop outs (sounds like ghastly modern art) Are you sure about the gender of the other two ? The supracaudal curls under in Ms - compare all four. Also males tails are much thicker & longer. Depends how much younger they are - poss. too young to tell.
Regards
Tom