The only information that I could find stated that it takes 3-4 years for T. shanjing to reach sexual maturity. Just for a comparison T. verrucosus only take a year and a half to reach sexual maturity. If you have any questions you can PM me and I cand send you the link where this information was obtained.
I have a shanjing of 13cm and his cloaca is out (bigger every day) and I´ve seen thats a female and it its reaching his sexual maturity but in two years I´m gonna study out of the country and in that moment I will have to say goodbye to all my newts and focus in the studies just! I want to reproduce t.shanjing before that.. i have only 2years! if there is any problem if the male is bigger and older that the female? with 13cm its you many years in my female?