Cheers, thought I'd share so that people can know you can sex ornatum without having to vent them. The black patch is quite apparent in yours, and certainly in larger specimens it should be even easier to tell. It surprises me that people with big ornatum specimens (5", 7", even 9" I've read about) seem to be completely unable to differentiate them.Great post, it prompted me to look back at photos of my ornatum juvies to see if the dorsal dimorphism id tool is apparent at a small size.
By the way, what pH do you keep yours at?