My partner has 2 common musk turtle and was wondering the sexes of them? Have taken a photo of each the best I could get of them. http://m.flickr.com/#/photos/[email protected]/5893992299/ http://m.flickr.com/#/photos/[email protected]/5893992971/
The inside surface of female hind legs tend to be smoother.
Based on the wide cranial (toward-the-head) end of the tail, the barbed tail tip, and the spiny leg scales, I'm saying: Male.
Your turtle look too small/young to sex. With Sternotherus odoratus, secondary sexual characteristics normally start to develop about 3.25" - 3.5" If a male, the tail will begin to lengthen very noticeably. The vent will extend past the rear edge of the carapace.