99% of all Moray species are unidentifiable, as male/female, without extensive medical tests.
If I remember correctly, there have been few instances where certain species have bred...never ending up with a maturing egg sack.
Dragons have never been bred. I had my Dragon for going on 8 years and went over every piece of information I could find (online, as well as years of contact with Shedd Aquarium) and could never find any instance where breeding them had ever come close.